Unnatural situation, my ass. When I was that age I was worried about soil erosion, overfishing, acid rain, desertification, the greenhouse effect, global political instabilities, deforestation, air- and water pollution, population growth, nuclear waste, overuse of fertilizers and pesticides, and a dozen other 'unnatural situations' that are still problems today (and that I'm still worried about). So here's my message to the YouTube generation: if you have too much time on your hand, and have already re-applied make-up three times today, why don't you talk about these infinitely more pressing problems? Because somebody could expect you do something about it?
And how 'natural' do you think YouTube is to begin with, maybe we better shut it down - I am sometimes very sure it will cause the end of the world as we know it.
Following some further links, I eventually came via another video titled "Did Nostradamus predict the LHC will create a Black Hole?" to a site called revelation13.net where you can read the following nonsense
"But perhaps creation of a black hole is a holographic parallel to the world reaching 6.66 billion population in 2008, and the rise to power of the Antichrist in Russia. If a black hole is created by LHC, then initially it might not be noticed, but it could gravitate to the center of earth and start swallowing the earth's core, perhaps over years. Perhaps such an event could be the cause of the Mayan calendar prophesy of the December 2012 destruction of earth. Lets hope for the best in this situation. If that should happen then nothing could be done about it. I think it is an interesting coincidence that CERN is turned on as the world population reaches 6.66 billion (in April 2008), 666 being the number of the Antichrist, and as the possible Antichrist Putin reached 666 months age in April 2008. Note that 666 is the number of the Antichrist in Revelation 13, the Antichrist or Beast being a Satanic imitation of Christ. In Greek, the original language of the Bible's New Testament, each letter is also a number, and therefore a word can be connected to a number by adding the letter-numbers."
And another great find is this: Black hole eating the earth, artist's impression
And what am I doing while the end of the world is coming close and the antichrist is apparently on his way? (Or is it 'her way'? Does the antichrist have a penis? Anybody knows?) Well, what I was doing today, besides wondering whether the antichrist has a penis, is preparing a colloq I'm supposed to give next week about, guess what, black holes at the LHC. (Look at this, they've even put together a poster, isn't that nice?) Too bad I can't download the above video, I'd have loved to embed it, it is just hilarious.
So, here is again all the reasons why the LHC isn't going to create a black hole that will cause the end of the world:
- To begin with, please notice that the creation of a black hole at the LHC is *not* possible in the standard framework of Einstein's theory of General Relativity. To produce black holes at the energies LHC can reach, it needs a modification of General Relativity at small distances. This could potentially be the case if our world had large extra dimension. There is however no, absolutely no, evidence so far this is really the case. The scenario is pure speculation, a hypothesis, a theory, or call it wishful thinking [1].
- It is not only that there must be compactified extra-dimensions, but the parameters of that model (their size and number) have to be in the right range. We know that the case with one dimension is excluded, and two should also already have shown up in sub-mm measurements, so this case too is strongly disfavoured. There are further various constraints from astrophysics that put strong bounds on the cases with three and four. But most importantly, there is no good reason known why these extra-dimensions should have the radius they need to have so quantum gravity is observable at the LHC - no reason other than it would be nice to have it shown up at these energy scales.
- Now to come to the issue of the black holes should they be created. Hawking showed in '75 using quantum field theory in the curved spacetime caused by a collapsing matter distribution that black holes emit thermal radiation. The temperature of this radiation is inverse to the radius of the black hole. The black holes that would be produced at the LHC would be extremely tiny, ~ 10-18 meters, and thus be extremely hot ~ 1016 K (that's a 1 followed by 16 zeros). They would decay within a time scale of roughly 1 fm/c, that is 10-23 seconds. They would not even reach the detector, instead they would decay already in the collision region. The only thing that could be measured are the decay products.
- The temperature of these black holes is so hot, they can not grow even if they pass through matter of very high density, like e.g. a gluon plasma or a neutron star. The mass gain from particles coming in the black hole's way (which depends on the density) is far smaller than the mass loss from the evaporation. The density of the earth is further several orders of magnitude smaller than that of nuclear matter, so there is no way the black hole could grow. Even if you assume the black hole has a high γ-factor (and thus experiences a higher density), this is not sufficient to enable it to grow.
- Hawking radiation is *not* a quantum gravitational effect. Hawking's calculation uses two very well known ingredients that are classical General Relativity and quantum field theory. It is true that we do not know quantum gravity, but quantum gravitational effects would only become important in the very late stages of the decay, when the black hole comes into the quantum gravitational regime. This would then affect the observables (and this ambiguity is thus somewhat of an annoyance), but it does not mean the black hole could grow. The reason is that if the black hole grew, it would come into the regime where Hawking's calculation applies to very good approximation, and it would lose mass as predicted. The scale for quantum gravitational effects to be important is the curvature at the horizon, which falls with M/R3 when the black hole grows, where M is the mass of the black hole and R is its radius (which again is a function of the mass).
As to the claim that there are 'people' who doubt black holes radiate, let me first reduce 'people' to 'physicists' since there are apparently also 'people' who doubt that the earth is more then 20,000 years old, or is a sphere (at least to very good accuracy). I know exactly no physicist who doubts that black holes radiate. The one work that I know of has sometimes been referred to is that by Adam Helfer. However, even he states in his paper (gr-qc/0503053) explicitly: "[These results] do not, as emphasized above, mean that black holes do not radiate [...]" [2]. - As has been said many times before, the earth is constantly hit by cosmic rays which undergo in interactions with particles in the earth's atmosphere collisions with a higher center-of-mass energy than the LHC will reach. If it was possible to produce a black hole this way which would then swallow the earth, this would not only very likely already have happened some billion years ago, but we should also see stars disappearing more often, especially neutron stars because of their high density. There is no evidence for that.
- It has then further been argued that the black holes at the LHC would be created in a different center of mass system, and thus not have the same average velocity with respect to the earth. This is correct but there are two points to be said here.
For one, the protons at the LHC will be accelerated to 99.9999991% of the speed of light, which is really fast. I mean, really. If you bang them together it is extremely unlikely the created particles will be in rest or even slow moving relative to the earth. Indeed, as Stefan has explained very nicely previously, their velocity will typically be far higher than the escape velocity of the earth. Pictorially speaking, consider a car crash. Things usually fly around quite a lot, already at 0.0000001% of the speed of light.
Second, even for the few black holes for which that wouldn't be the case, again, they would decay even before they hit the detector. In any case they would definitely not collect in the middle of the earth (or 'gravitate to the center of the earth' or whatever). This is a totally absurd idea that I have however come across several times. It is absurd because the center of the earth would generally not be on the produced object's trajectory (having an initial velocity), and even if it was they wouldn't stop in the center of the earth, why should they? Ever heard of energy conservation? As said previously, they are far to small (cross-section to small) to interact noticeably with the earth's matter so they wouldn't slow down. (If one really pushes it one can now go and estimate how long it would take them to slow down until they get stuck and so on. But frankly, this scenario is already so absurd that such a speculation is totally moot, and an utter waste of time, mine and yours.) - About the claim that the LHC's risk report is biased because it has not been performed by people at "arm's length". Yes, to get a reasonable report about the difficulties the LHC might be facing I would think you ask experts. These experts are usually people working in the field. Would you prefer them to be random sampled from a phone-book? I honestly do not understand why anybody would think people working in theoretical physics have a larger interest in destroying the planet than other human beings.
To be somewhat cynical here, you'd instead think that a lot of theoretical physicists should be really nervous about the LHC because it will test their theories. And no matter what, very many of these theories will be outruled, dead, speculations no longer viable. One of these theories that can be tested is the one with large extra-dimensions. And if it isn't found hundreds of people who have worked on it must face that they have wasted their time, their publications do not describe nature, and the topic is no longer something you can use for a grant proposal. - Finally, let me say that there is always some amount of uncertainty in everything we do. Yes, there is the possibility we are all wrong. There is also the possibility that you wake up tomorrow morning an have turned into a monstrous bug, because a cosmic ray has modified some virus to being capable altering your DNA. Or, as Arkani-Hamed put it so aptly in the recent NYT article: There is some minuscule probability, he said, “the Large Hadron Collider might make dragons that might eat us up.”
I, and I believe many of my colleagues, would really appreciate if the media - TV, print and online - would not support such catastrophe-scenarios and scientifically completely absurd scary stories just because they sell well. There is, in the community, no argument about whether mini-black holes at the LHC are a risk worth worrying about. The answer is simply no, they are not. The story about black holes created in particle colliders that swallow the earth came up first time in '99 regarding RHIC, so it has a long beard in 2008, and it's getting longer every day. If you are running out of topics for the science section, why don't you go and ask some scientists for inspiration?
I have no specific relation the theories investigated here, in fact, not being influenced by subjective preferences is part of what it means to be a scientist (whether we like that or not). I'm not telling you what I wrote here because I want money or publicity for collider physics, or any other reason of personal advantage you could accuse me of. I am telling you that just because black holes at the LHC is not something you should worry about. Worry about some real problems instead.
Further reading (strongly recommended before asking redundant questions):
Note added May 2nd: Clifford from Asymptotia asked me to clarify that with 'quantum gravity' I mean a theory in which gravity is quantized.
[1] And if you don't take into account the presence of large extra dimensions, you will find correctly that there is a factor 1032 missing. Before you suggest this factor has been overlooked in hundreds of peer-reviewed publications, maybe consider redoing your calculation.
[2] It seems to me that even if one bought his approach they would evaporate only faster. It's hard to say though because he states "it is unrealistic at present to expect to be able to make quantitative theoretic predictions".
TAGS: LHC, PHYSICS, BLACK HOLES, NOSTRADAMUS, NONSENSE, PARTICLE PHYSICS
LOL! Okay, but couldn't the LHC destroy the world in lots of other ways, ways that you haven't considered?
ReplyDeleteWhat if the high levels of proton speeds causes mutations in viruses? And they escape and kill everybody? And what about bacteria? IS THE LHC sterilized?
By the way, regarding your juvenile opinions on environmentalism and all that, I think it is hilarious that physicists get off on treating engineers as crackpots when they express their uneducated opinions on physics, but don't see any problem with a physicist, (who's never designed a manufacturing plant, know nothing about chemical engineering, and have never applied for an air quality permit and has no degrees in any sort of engineering or chemistry etc.) expressing their heart-felt opinions on the environment.
Uh, by "juvenile opinions" of course I mean the opinions you had as a youth.
ReplyDeleteHi Carl,
ReplyDeleteI'd guess 1.9 K and 10^-13 atm is pretty much sterile ;-)
I actually don't know what you are referring to with physicists treating others as crackpots. I certainly have no problem with anybody expressing heartfelt opinions, and I don't think I've ever called somebody a crackpot? I am really sorry for all those people who are sincerely worried, having had plenty of worries myself as a teenager many of which later turned out to be due to exaggerated and/or unscientific reporting (growing up in a time of AIDS, Czernobyl, and Germany having lots of environmental problems one got to read and hear a lot that 10 year olds could get wrong). Yes, I am still worried about many environmental problems, but I usually don't write scary stories about them or declare the end of the world is due this year exactly because my knowledge is rather limited. My concerns about these issues btw lie dominantly on the political side (e.g. do our institutions manage to deal with them appropriately and in a timely manner). I am not sure if that addresses your comment but my problem is that unbalanced news reporting rather generally makes sensible discussions very hard, and reporting with the only purpose to scare people is just inappropriate. Best,
B.
PS: Also interesting, spell-check wants to replace Czernobyl with Cleanable.
I guess the only black hole would be the one in the standard theory if they don't find traces of Higgs.
ReplyDeleteBeautiful girl in the video though. Beauty should always be excused in my opinion:)
P.S Congratulations Bee for another detailed and complete post.
Hi Bee,
ReplyDeleteAnother great post with even more explained. To be truthful though it was the venom I enjoyed the most and it was long overdue. I for one think too often the scientific community pussy foots around with people who have no intention in attempting to understand anything except their own unfounded opinions. There are many who are motivated by irrational fear and I must say I feel sorry for them, for like those that are afraid of heights, flying, confined spaces, rollercoasters or the boogey man, as we can do nothing for them, other then hope they seek out the help they need.
However, there is a second group that I am more wary of and those being the ones with some agenda other then what they would have us perceive as being only legitimate concern. They use unethical tactics, such as extreme exaggeration or even outright lies. They post what looks like informed and concerned web sites, which often screen comments before release. This serves to give one an unbalanced perception, which of course is the whole point to the tactic of censorship. They also find there way into print media, radio and television with practices much the same. These are the ones that shouldn’t be trifled with. They should be the ones threatened with civil and even criminal action as to show that there are consequences for their actions; and they are not immune simply because they claim their intent is to save us all and for our own good.
So as a first step, I would recommend those at CERN not only address this law suit, yet go further and file a counter claim, seeking damages for themselves and the related scientific community in general, whom these people have both slandered and libeled. It’s clear to me what must be done when the fox is in the hen house. I say stop with the defensive poster and go on the offence, for otherwise you play by rules they don’t hold themselves to and depend you will.
Best,
Phil
P.S. I guess Uncle Al is having a effect on me:-)
You may count me in for number 4: I am not 100% convinced that if black holes are produced at LHC (e.g. in some large extra dimensions scenario) the Hawking calculation applies to them: In that calculation you look at a free quantum field at infinity in the spacetime of a semi-classical black hole.
ReplyDeleteThe microscopic black holes LHC could produce however would not be semi-classical, the curvature on the horizon would actually be Planck scale. Thus pure Einstein gravity is unlikely to be the correct description close the the horizon and the free quantum field might be a bad approximation as well.
Furthermore, the black hole in the Hawing calculation is nearly static: We see the radiation but what we compute is QFT in a fixed background geometry. For macroscopic black holes this is an excellent approximation and there you use conservation of energy to conclude that the bh gets smaller.
For the microscopic bh you are --- as you explain --- close to the moment where disappears. Again, this is obviously not quasi static and this raises the issue of remnants and how you get rid of them (a quantum gravity question probably).
All I am saying is that I don't think we have a very well controlled theory of microscopic black holes and the last stages of their decay. But still all the other points are very valid and thus even is the black hole (or some remnant) stays with us it would not be of any danger since I would expect it to look pretty much like any other elementary particle.
Hi Bee,
ReplyDeleteNice post! This guy doubts that a BH radiates:
http://de.arxiv.org/abs/gr-qc/0607137
It seems that he submitted a first version of the above paper to PRL. It was rejected, of course. It is amazing that PLA dares to publish that!
Flavio
Hi Flavio,
ReplyDeleteThanks! Will have a look. At first sight it seems he doesn't like the usual vacuum definition and therefore wants to reinterpret the result (he gets the usual temperature, see Eq. (61)). Best,
B.
I think Robert hit the nail on the head. Semiclassical black holes are created by the old fashion way of matter accumulation and are of no concern to the LHC. This is the type of black hole that 99% of the public is aware of. The microstate black hole is a different animal in that it is associated with the quantum gravity regime (Planck scale) which again is unlikely at LHC. There is simply not going to be a microstate black hole created which is near Planck density at the LHC level. Scattering processes will prevent this all the way up to GUT level.
ReplyDeleteHi Robert,
ReplyDeleteYes, the exact characteristics of the evaporation are not very well understood. This is one of the reasons why I don't work on the topic anymore. One can make all kinds of exact calculations of greybody factors and bulk/brane ratios and include supersymmetry and rotation and whatnot. But point is, how the final decay looks like is unknown. It is also unclear how the evaporation affects the temperature, since the black hole doesn't really have time to thermalize. So there's two possibilities that people consider: it either just decays instantaneously without the temperature changing. Or the temperature adjust after each emission (not in the microcanonical approach that Hawking used, but in the macrocanonical, so it doesn't have the unphysical divergence). Either way, they evaporate. What I'm saying is just that I found it's at a point where one would have to just go and measure before adding more and more details. One should also take into account that since the LHC is a hadron collider almost all of the black holes produced will have the smallest possible masses close by the threshold and essentially only make the final decay about which we know the least. The heaver ones are exceedingly rare.
Best,
B.
Hi Mark,
ReplyDeleteDepends on where the Planck scale is. As I said above the QG effects get weaker with the com energy (mass of the hole) increasing, so the not-classical effects go with powers Mass/Energy. As I wrote above I agree with Robert that for those BHs that are really directly planckian one doesn't know much, and I actually don't think we will know much until we have a theory of qg. Maybe you find Giddings summary interesting reg. semi-classical approx (see also references therein). Best,
B.
Abandon civilization to avoid UNKNOWN HAZARDS! Plastic water bottles are bad. Goatskins are good (dialectic obtains the goat part). Enviro-whiners ooze fear without comprehension, i.e., religion.
ReplyDeleteIs the antichrist circumcised? (especially important if the antichrist is a girl via CP inversion)
Off-center [lightspeed - epsilon] nuclear collisions create positively charged Kerr-Newman black holes. As electrons ultra-relativistically swirl in they will be electromagnetic pulse weapons imploding every iPhone, iPod, and X-Box on Earth. Know the fear, do it anyway.
Thanx Bee for the refs. I think it may be correct that all a microstate black hole wants to consume are thermal photons and not matter. Perhaps its the result of early cosmological conditions (QG). Who knows?
ReplyDeletemark
Thanks for another great post B; it must be annoying to have to repeat oneself over and over ...
ReplyDeletePhil - your second paragraph "However...good" seems to describe the present US administration almost exactly. Very scary indeed; unfortunately, they seem immune to prosecution at the moment.
Best.
Thanks :-) Well, I try to tell myself each time I repeat it, a few more people will get the message. Best,
ReplyDeleteB.
Hi Bee
ReplyDeleteThe material you post brings together valuable material on whether or not there would be a risk from the LHC. My comments are on a few points which I think weaken your argument, generally by appearing to be somewhat unfair. They are offered in the spirit of hoping the LHC can be shown to be safe and operate.
A few selections from your post and comments :
"…YouTube video "The LHC-- the end of the world again?" showing a teenage girl in a garden babbling (my emphasis)"
Incorrect argumentation - ad hominem
"When I was that age I was worried about soil erosion, overfishing, acid rain, desertification, the greenhouse effect, global political instabilities, deforestation, air- and water pollution, population growth, nuclear waste, overuse of fertilizers and pesticides, and a dozen other 'unnatural situations' that are still problems today (and that I'm still worried about)."
Incorrect argumentation - red herring
"So here's my message to the YouTube generation: if you have too much time on your hand, and have already re-applied make-up three times today…"
Incorrect argumentation - ad hominem
"Following some further links, I eventually came via another video titled "Did Nostradamus predict the LHC will create a Black Hole?" "
Incorrect argumentation - straw man. Because some clearly crazy people support one side of an argument doesn’t mean the argument is necessarily wrong.
"Hawking showed in '75 using quantum field theory in the curved spacetime caused by a collapsing matter distribution that black holes emit thermal radiation."
Can you be more precise in language? As a scientist - although not a physicist, but with a paper in Nature - to me in the scientific method, the use of “showed” means “empirically demonstrated”. I don’t think Hawking or anyone else has done this.
"About the claim that the LHC's risk report is biased because it has not been performed by people at "arm's length". Yes, to get a reasonable report about the difficulties the LHC might be facing I would think you ask experts. These experts are usually people working in the field. Would you prefer them to be random sampled from a phone-book (my emphasisis)? "
Incorrect argumentation - straw man. That’s not the only alternative. Richard Posner in his Oxford University Press -published book gives another recommended makeup of an assessment panel - and it’s not just physicists.
"Finally, let me say that there is always some amount of uncertainty in everything we do. Yes, there is the possibility we are all wrong."
But not all errors have this particular worst-case scenario attached to them.
"There is also the possibility that you wake up tomorrow morning an have turned into a monstrous bug, because a cosmic ray has modified some virus to being capable altering your DNA. Or, as Arkani-Hamed put it so aptly in the recent NYT article: There is some minuscule probability, he said, “the Large Hadron Collider might make dragons that might eat us up.”"
Incorrect argumentation - straw man.
"I, and I believe many of my colleagues, would really appreciate if the media - TV, print and online - would not support such catastrophe-scenarios and scientifically completely absurd scary stories just because they sell well. "
Incorrect argumentation - ad hominem. How do you know that is their motive?
"If you are running out of topics for the science section, why don't you go and ask some scientists for inspiration?"
Leave war to the generals? Lucky Kennedy didn’t do that in the Cuban missile crisis.
Regards
LW
Hi LW,
ReplyDeleteWell, thanks for your thoughtful comment. You have however misunderstood my mentioning of the YouTube videos. This is not an 'argument' of any kind, and I have never pretended so. It is simply a demonstration of what you find out there.
- If you think 'babbling' is an 'ad hominem' attack, I apologize profoundly.
- It is not a red herring, because I don't discard discussing the actual topic for it.
- The Nostradamus quote isn't a straw man argument because I don't 'attack' it in exchange for the actual point. In fact, you might have noticed I don't comment on it at all.
- Again, you completely misunderstand my mentioning of the YouTube generation. It is not their argument that I am 'attacking'. I am just expressing my opinion that they could use their time better, and I think I make it pretty clear that it is my opinion.
- If you think 'showed' means something with 'seeing' empirically, then maybe 'derived' would have been more exact? However, I am very used to the word 'show' meaning to show from A follows B.
- I see. You are correct. It was meant to be a joke.
- It is not an ad hominem attack. First because this too is not part of the argument to begin with. Second because I do not claim this is their motive. I say, if this is the motive, then they shouldn't fall for it.
- I didn't say to leave it over to the scientists. Gee, certainly not! I was just suggesting that instead of repeating the same stories over and over again to maybe ask some scientists what they would like to see reported on.
Best,
B.
Btw, the girl in the first video has in my perception a somewhat confused line of thought, but she doesn't say anything plainly wrong. I think she's reading off the more complicated parts somewhere. Best,
ReplyDeleteB.
Hi Bee,
ReplyDeleteThere is a post on ArXiv tonight, "Accelerator Disaster Scenarios, the Unabomber, and Scientific Risks." Seems that fear of accelerators destroying the world has a history. The article is also an account of the author's personal experiences in physics -- so it's not a short read.
Best, Kris
You can download youtube (and other) videos with the help of this site. Or grab them from cache while you're still on the youtube page and the video has finished downloading (on macs the location is something like /var/tmp/folders.501/TemporaryItems/FlashTmp0).
ReplyDeleteHi Kris,
ReplyDeleteThanks for pointing this out, I would probably have missed it! I will give it a read. Best,
B.
Hi Ivan,
ReplyDeleteThanks! I should probably say, by now I have like three different versions of that video. So thanks everybody for the help! And yes, it will go into my next week's talk (amazingly enough, I managed to embed it into pdflatex). Will let you know what the audience thinks :-)
Best,
B.
The article by listed by Kris Joe Kapusta( I included another point to consider in context of Joe) is a good read. I learnt of him through Peter Steinberg and his lecture in Flicker up loaded by him on August 9, 2005.
ReplyDeleteThis article goes to the point I made earlier, by how one might scoff at the ridiculousness of the idea of strangelets( how they came about in relation to the issue at hand)about what scientists actually know outside of those who are directly dealing with the work.
What is important, is that "LW" is being placed their amongst the originations of the research that was coming out. "A Lawyer" and "a scientist?"
Now we know how Peter Steinberg is dealing with this directly and how Cern is also answering the process most intelligibly.
It did lead to a greater understanding by looking into the QGP process that Joe is talking about in it's development, also, leads one to consider the context of what is evident in Grans Sasso and the area Joe is now working.
This relationship is what I found in concert with the Pierre Auger experiments( the awarenss of cosmic rays and John Ellis's work, and the issues of GZK cutoff and the historical development of the Flys Eye, and the "Oh my God Particle" issue then.
I would caution then those scientist who clamour with such vociferously about the ridiculousness of what what is being done in terms of the challenge of law in that issue, is also the awareness of what scientists have now learnt retrospect, that stranglets had been proved not to exist and that the very term "God Particle," is, "the incredible nature of scientific research" that discounts the term in face of what it now knows.
So what is now incredulous in the news and the article that passes from one blog to the next heralded research into the new things that are relevant in the collision process?
I am not in support LW's challenge just that it be taken into consideration with a little more respect. The challenge is an adverse way in which to answer all the conditions and provide for the benefits of checking over the current situation with the relevant information. Nothing wrong with detailing the facts as we now know them. I believe Cern is already dealing with them responsibly. They did it with the strangelets.
Is that the best you have... I will focus on the micro black hole argument, that is what the $500 contest at LHCConcerns.com is about , present a proof of 5% or lower risk from micro black holes... Should be easy, correct?
ReplyDelete[quote]So, here is again all the reasons why the LHC isn't going to create a black hole that will cause the end of the world:
1. To begin with, please notice that the creation of a black hole at the LHC is *not* possible in the standard framework of Einstein's theory of General Relativity. To produce black holes at the energies LHC can reach, it needs a modification of General Relativity at small distances. This could potentially be the case if our world had large extra dimension. There is however no, absolutely no, evidence so far this is really the case. The scenario is pure speculation, a hypothesis, a theory, or call it wishful thinking [1].
[/quote]
Sorry, CERN predicted creation of up to 1 micro black hole per second. Have CERN publicly and strongly completely retract that prediction and I will give your argument more credit. Currently, you are talking out of both sides of your mouth. CERN either predicts the creation of micro black holes or they do not. They do. Further, the March 2005 RHIC bose-nova implosion created a Bose-Einstein condensate and thousands of atoms could not be accounted for. According to one Nobel prize winner it was "probably not a black hole". I hope he was correct. Because what ever was created, it was stable and it disappeared.
[quote]
2. It is not only that there must be compactified extra-dimensions, but the parameters of that model (their size and number) have to be in the right range. We know that the case with one dimension is excluded, and two should also already have shown up in sub-mm measurements, so this case too is strongly disfavoured. There are further various constraints from astrophysics that put strong bounds on the cases with three and four. But most importantly, there is no good reason known why these extra-dimensions should have the radius they need to have so quantum gravity is observable at the LHC - no reason other than it would be nice to have it shown up at these energy scales.
[/quote]
This is supposed to be convincing... to who?
[quote] 3. Now to come to the issue of the black holes should they be created. Hawking showed in '75 using quantum field theory in the curved spacetime caused by a collapsing matter distribution that black holes emit thermal radiation. The temperature of this radiation is inverse to the radius of the black hole. The black holes that would be produced at the LHC would be extremely tiny, ~ 10-18 meters, and thus be extremely hot ~ 1016 K (that's a 1 followed by 16 zeros). They would decay within a time scale of roughly 1 fm/c, that is 10-23 seconds. They would not even reach the detector, instead they would decay already in the collision region. The only thing that could be measured are the decay products.
[/quote]
Hawking Radiation has been disputed by no less than 3 rigorous peer reviewed studies that found no basis in science for such a conclusion. This is science fiction that requires Einstein to be doubly wrong in Professor Hawking's opinion. And we should believe professor Hawking why, because he has had how many theories proven correct correct in his very long career, he has won how many Nobel prizes since he completed his academic career with a sterling C average? Give me a break.
[quote] 4. The temperature of these black holes is so hot, they can not grow even if they pass through matter of very high density, like e.g. a gluon plasma or a neutron star. The mass gain from particles coming in the black hole's way (which depends on the density) is far smaller than the mass loss from the evaporation. The density of the earth is further several orders of magnitude smaller than that of nuclear matter, so there is no way the black hole could grow. Even if you assume the black hole has a high γ-factor (and thus experiences a higher density), this is not sufficient to enable it to grow.
[/quote]
And you know better than Professor Rossler who has been described by the 'Zero Risk' crowd as prestigious but, eminent but, world recognized but... And Albert Einstein was 'just a grad student'. Professor Rossler is one of the worlds most respected scientist geniuses, his list of scientific accomplishments is staggering. He did the math. 50 months accretion time. Where is the rigorous peer review rebuttal? Where is LSAGs Earth Accretion math? LSAG writes that they do not assume that micro black holes will be stable. So where is the rigorously peer reviewed Accretion math? It is only the fate of the planet, no math?
[quote] 5. Hawking radiation is *not* a quantum gravitational effect. Hawking's calculation uses two very well known ingredients that are classical General Relativity and quantum field theory. It is true that we do not know quantum gravity, but quantum gravitational effects would only become important in the very late stages of the decay, when the black hole comes into the quantum gravitational regime. This would then affect the observables (and this ambiguity is thus somewhat of an annoyance), but it does not mean the black hole could grow. The reason is that if the black hole grew, it would come into the regime where Hawking's calculation applies to very good approximation, and it would lose mass as predicted. The scale for quantum gravitational effects to be important is the curvature at the horizon, which falls with M/R3 when the black hole grows, where M is the mass of the black hole and R is its radius (which again is a function of the mass).
[/quote]
Hawking again, not credible. The GLAST satellite will look for signs of Hawking Radiation this summer, are you planning to start up the Large Hadron Collider before this satellite might fail to find the mythical Hawking Radiation. The following is what one professional physicist that I highly respect said of Hawking Radiation and possible quantum effects on micro black holes...
[quote]
"Hawking Radiation" is a hoax. Quantum theory should actually likely require a blackhole to grow larger, not smaller, if it were to effect a blackhole. Here's why.
Separating "virtual particle pairs" into real particles is not difficult, nor is creating antiparticles.
We routinely make antiprotons at Fermilab, etc. We slam high-energy protons into a Nickel target, with kinetic energy of about 2 orders of magnitude more than the rest-mass of a proton [about 0.94 GeV]. Out pop all kinds of particles and antiparticles, including antiprotons, which we magnetically separate, store, and later accelerate and collide into protons.
These scenarios always require an input of energy at least equal to the rest-mass of the particles created. For the radioisotope, this energy comes from the mass of the nucleus itself, which is reduced slightly when the positron is emitted. For making antiprotons, it comes from the kinetic energy of the proton beam striking the target.
Hawking's idea of evaporating black holes does not require input of energy to create particles. Instead, he believes that two particles [the particle and its antiparticle] will come into existence at the 'event horizon' as virtual particles, with one falling into the black hole, the other wandering away [as "Hawking Radiation"]. Because the one that wandered away became real, the one that fell into the black hole must have the equivalent of negative mass, thereby reducing the mass of the blackhole, preserving the total mass of the system.
That is the hoax. Negative mass. No such thing. If there were, the negative mass particle would more likely be repelled from the black hole [the opposite sign would make for gravitational repulsion, not attraction], not falling into it. The net result would be that black holes would spontaneously slowly grow larger, not evaporate, robbing via quantum tunneling from nearby matter. However, I believe they would just sit there unless matter directly fell into them. Either way, "Hawking Radiation" would not exist.
It is, of course, utter lunacy to use as a "safety argument" the idea that "Hawking Radiation" will evaporate the microblackholes they hope to make in the ATLAS detector. [/quote]
[quote] As to the claim that there are 'people' who doubt black holes radiate, let me first reduce 'people' to 'physicists' since there are apparently also 'people' who doubt that the earth is more then 20,000 years old, or is a sphere (at least to very good accuracy). I know exactly no physicist who doubts that black holes radiate. The one work that I know of has sometimes been referred to is that by Adam Helfer. However, even he states in his paper (gr-qc/0503053) explicitly: "[These results] do not, as emphasized above, mean that black holes do not radiate [...]" [2].
[/quote]
Talk to me about science that is NOT REFUTED by rigorous scientific studies over and over and find NO BASIS IN SCIENCE. Give up Hawking Radiation, LSAG has "we do not assume that micro black holes will evaporate..." and your peers have. Hawking Radiation is not science. It is rigorously disputed speculation that has no basis in reality.
[quote] 6. As has been said many times before, the earth is constantly hit by cosmic rays which undergo in interactions with particles in the earth's atmosphere collisions with a higher center-of-mass energy than the LHC will reach. If it was possible to produce a black hole this way which would then swallow the earth, this would not only very likely already have happened some billion years ago, but we should also see stars disappearing more often, especially neutron stars because of their high density. There is no evidence for that.
[/quote]
Your own LSAG (LHC Safety Assessment Group) presented to the University of Berkley not too long ago and conceded that cosmic ray impacts with Earth would send ALL particles created safely into space. Even the 1999 RHIC safety study conceeded that cosmic ray impacts are not equivalent of collider collisions. Why did CERN not release a promissed safety report from LSAG. Because they did not want the creme of the worlds physicists to tear it apart, so they send Physics graduate students to peddle weak, non-peer reviewed science on blogs?
Now you want me to believe that a cosmic ray hitting a stationary particle would focus the energy to a single point the same way that a collider smashes same mass, exact same speed, exact opposite vector and in some cases exactly center mass collisions with particles traveling each at 99.9999991% the speed of light for a net collision speed of almost 2C focusing the energy precisely to a single point, and sometimes these collisions will involve protons with anti-protons. And you want me to believe that is the same as a stray proton with up to 10^20 eV of energy hitting a relatively stationary particle on Earth. I read the 1999 RHIC safety study, they admit that the momentums produced by cosmic rays do replicate head on collider collissions. Did you read the 1999 RHIC study? Are you trying to make false arguments? Or do you truly not understand basic physics?
[quote] 7. It has then further been argued that the black holes at the LHC would be created in a different center of mass system, and thus not have the same average velocity with respect to the earth. This is correct but there are two points to be said here.
[/quote]
Thank you.
[quote] For one, the protons at the LHC will be accelerated to 99.9999991% of the speed of light, which is really fast. I mean, really. If you bang them together it is extremely unlikely the created particles will be in rest or even slow moving relative to the earth. Indeed, as Stefan has explained very nicely previously, their velocity will typically be far higher than the escape velocity of the earth. Pictorially speaking, consider a car crash. Things usually fly around quite a lot, already at 0.0000001% of the speed of light.
[/quote]
I don't know if every single EXTREMELY DENSE micro black hole created will be captured by Earth's gravity. I would like to know. Because if even the first is likely or virtually assured to be captured, then shutting down the experiment as CERN promised in response Professor Rosslers very strong concern, will be of no use!
[quote] Second, even for the few black holes for which that wouldn't be the case, again, they would decay even before they hit the detector. In any case they would definitely not collect in the middle of the earth (or 'gravitate to the center of the earth' or whatever). This is a totally absurd idea that I have however come across several times. It is absurd because the center of the earth would generally not be on the produced object's trajectory (having an initial velocity), and even if it was they wouldn't stop in the center of the earth, why should they? Ever heard of energy conservation? As said previously, they are far to small (cross-section to small) to interact noticeably with the earth's matter so they wouldn't slow down. (If one really pushes it one can now go and estimate how long it would take them to slow down until they get stuck and so on. But frankly, this scenario is already so absurd that such a speculation is totally moot, and an utter waste of time, mine and yours.)
[/quote]
Excuse me, but you are repeating weak and disputed arguments... If it is scientific, then officially release it and have it peer reviewed. If you can not, then perhaps all you can do is have Physics grad students peddle this 'stuff' on blogs.
[quote] 8. About the claim that the LHC's risk report is biased because it has not been performed by people at "arm's length". Yes, to get a reasonable report about the difficulties the LHC might be facing I would think you ask experts. These experts are usually people working in the field. Would you prefer them to be random sampled from a phone-book? I honestly do not understand why anybody would think people working in theoretical physics have a larger interest in destroying the planet than other human beings.
[/quote]
LHC Safety Assessment Group never release a report. There is no report. That is a very strong statement in it self. What I am responding to now, is this the LSAG safety report? Are the scientists who wrote it are not willing to defend it? I don't blame them.
[quote] To be somewhat cynical here, you'd instead think that a lot of theoretical physicists should be really nervous about the LHC because it will test their theories. And no matter what, very many of these theories will be outruled, dead, speculations no longer viable. One of these theories that can be tested is the one with large extra-dimensions. And if it isn't found hundreds of people who have worked on it must face that they have wasted their time, their publications do not describe nature, and the topic is no longer something you can use for a grant proposal.
[/quote]
I don't know how many scientists I have read that said, "No danger", of course I have not bothered to look into it myself, I am busy. Of course, according the legal action, employees of CERN are requested to refer to the risk as zero, regardless of personal opinions.
[quote] 9. Finally, let me say that there is always some amount of uncertainty in everything we do. Yes, there is the possibility we are all wrong. There is also the possibility that you wake up tomorrow morning an have turned into a monstrous bug, because a cosmic ray has modified some virus to being capable altering your DNA. Or, as Arkani-Hamed put it so aptly in the recent NYT article: There is some minuscule probability, he said, “the Large Hadron Collider might make dragons that might eat us up.”
[/quote]
Fine, at least prove the risk is less than 5%, then I can sleep at night believing my children may have some chance of growing old.
There is a $500 challenge, just prove 5% or less risk with respect to micro black holes. How many grad students are so well paid that you could not use $500?
[quote]I, and I believe many of my colleagues, would really appreciate if the media - TV, print and online - would not support such catastrophe-scenarios and scientifically completely absurd scary stories just because they sell well. There is, in the community, no argument about whether mini-black holes at the LHC are a risk worth worrying about. The answer is simply no, they are not. The story about black holes created in particle colliders that swallow the earth came up first time in '99 regarding RHIC, so it has a long beard in 2008, and it's getting longer every day. If you are running out of topics for the science section, why don't you go and ask some scientists for inspiration?
I have no specific relation the theories investigated here, in fact, not being influenced by subjective preferences is part of what it means to be a scientist (whether we like that or not). I'm not telling you what I wrote here because I want money or publicity for collider physics, or any other reason of personal advantage you could accuse me of. I am telling you that just because black holes at the LHC is not something you should worry about. Worry about some real problems instead.[/quote]
I don't think I will sleep well tonight. Will you?
JTankers
LHCConcerns.com
Hi JTankers,
ReplyDeleteThanks for your comment.
Sorry, CERN predicted creation of up to 1 micro black hole per second. Have CERN publicly and strongly completely retract that prediction and I will give your argument more credit. Currently, you are talking out of both sides of your mouth. CERN either predicts the creation of micro black holes or they do not.
It wasn't 'CERN' who made this prediction but Dimopoulos + Landsberg, but besides this you apparently have a problem with the word 'if'. It is a prediction IF the world has extradimensions and IF they have the right number and IF they have the right radius etc. (Besides this, the number one per second is somewhat outdated and has since then been corrected downward because the scenario is overly optimistic.)
Hawking Radiation has been disputed by no less than 3 rigorous peer reviewed studies
UUUh! AAAhh! Gee, three rigorous peer reviewed studies! I shiver for fear! Are those by the same two above mentioned people?
"Hawking Radiation" is a hoax. Quantum theory should actually likely require a blackhole to grow larger, not smaller, if it were to effect a blackhole. Here's why.
[...] That is the hoax. Negative mass. No such thing. If there were, the negative mass particle would more likely be repelled from the black hole [the opposite sign would make for gravitational repulsion, not attraction], not falling into it.
Your 'explanation' why Hawking radiaton can't work is a very sad example for popular science explanation gone wrong that I mentioned previously in this thread. The picture with the pair production at the horizon is very misleading. If you can, I encourage you to do the calculation. The brief explanation to your problem is the energy of the infalling particle is negative as measured by the observer at infinity because inside the horizon the time- and spacelike coordinates are exchanged so the energy has a sign change. This does not mean these particles anti-gravitate.
I don't know how many scientists I have read that said, "No danger", of course I have not bothered to look into it myself, I am busy.
What is that supposed to prove?
And you know better than Professor Rossler who has been described by the 'Zero Risk' crowd as prestigious but, eminent but, world recognized but... And Albert Einstein was 'just a grad student'. Professor Rossler is one of the worlds most respected scientist geniuses, his list of scientific accomplishments is staggering. He did the math. 50 months accretion time. Where is the rigorous peer review rebuttal?
My sincere apologies, but I have never heard of this this world respected genius. Btw, this argumentation is also called 'appeal to authority'. Anyway, it's nice somebody did the math. As I wrote in the text, I don't doubt you can do this calculation. What is there to rebut? If you make assumption A then you can calculate B. People do that all the time. It seems to me this is the same problem with the conditional statements you have with point 1.
Excuse me, but you are repeating weak and disputed arguments...
Well, thanks for letting me know it's me who repeats the weak and disputed arguments.
Now you want me to believe that a cosmic ray hitting a stationary particle would focus the energy to a single point the same way that a collider smashes same mass, exact same speed, exact opposite vector and in some cases exactly center mass collisions with particles traveling each at
I never said that, and I don't see any point repeating what I said above.
Why did CERN not release a promissed safety report from LSAG. Because they did not want the creme of the worlds physicists to tear it apart, so they send Physics graduate students to peddle weak, non-peer reviewed science on blogs? [...]
There is a $500 challenge, just prove 5% or less risk with respect to micro black holes. How many grad students are so well paid that you could not use $500?
I'm not a grad student. And I am very well paid, thanks.
Best,
B.
Are you telling me that the Earth is safe because you believe that Professor Hawking has proven that micro black holes evaporate. Is that what you are saying?
ReplyDeleteAre you telling me that you have not read the rigorous peer reviewed studies that found no basis in science to support such conclusions?
And you want me to believe you when you say "zero risk"? You can't even prove less than 5% risk.
Professor Hawking speculates that it might be possible for particles to travel back in time, Professor Albert Einstein considered such ideas to be paradoxical nonsense, not possible.
Professor Hawking speculates that black holes might sometimes shrink, decay, evaporate, again Professor Albert Einstein considered such ideas to be not possible, against the laws of nature.
Professor Hawking today speculates that it will be safe to create micro black holes on Earth in the Large Hadron Collider, because he believes that quantum fluctuations around black holes will steal energy from the black hole. He seems quite certain about his theory, while at the same time he dismisses and ignores his own peers who write rigorous peer reviewed studies disputing this theory as not supportable by science, disputes Professor Einstein who stated that not even light can escape a black hole, and apparently requires that vacuum energy does not exist. And Professor Hawking was recently quoted as suggesting that he should be awarded a Nobel prize for this idea. (Professor Hawking has never won a Nobel prize). ''' Credibility of Hawking Radiation is strongly disputed:'''
2008 ... this prediction is not without its problems... no very good responses to these concerns... completely alters the picture drawn by Hawking... http://arxiv.org/PS_cache/gr-qc/pdf/0503/0503052v1.pdf
2008 ... Max-Plank-Institut fur Astrophysik: The results indicate that on average, "low mass" black holes of less than a hundred million solar masses are still growing at a significant rate. http://www.mpa-garching.mpg.de/mpa/research/current_research/hl2004-7/hl2004-7-en.html
2004 ... it may be a long time before we have sufficient knowledge of quantum gravity to be able to calculate the correct answers for the logarithmic terms in the entropy. http://arxiv.org/PS_cache/hep-th/pdf/0409/0409024v3.pdf
2004 ... 9.9% average doubt, ranging from 0% to 50% doubt by 15 physicists polled: http://www.lhcconcerns.com/#James_Blodgett, even before much of the peer reviewed credible rejection of Hawking Radiation was published
2003 ... Yet this prediction rests on two dubious assumptions... no compelling theoretical case for or against radiation by black holes: http://arxiv.org/abs/gr-qc/0304042
1900s ... Albert Einstein's theories require that black holes only grow, they never shrink, not even light can exit a black hole
Recently when asked if the Large Hadron Collider was safe, Professor Hawking said "Particles from collisions far greater than those in the LHC occur all the time in cosmic rays, but nothing terrible happens.". What? (http://www.latimes.com/news/science/la-sci-hawking12apr12,1,3191870.story))
Even CERN's own LHC Safety Assessment Group has conceded the that cosmic ray impacts with Earth could not endanger Earth, because unlike paricles created by head-on collider collisions, cosmic ray created particles travel too fast to be captured by Earths gravity and are all safely expelled into space at relativistic speeds, and the same LSAG group stated that they do not assume that micro black holes will evaporate. But CERN never released any safety reports created by LSAG.
JTankers
LHCConcerns.com
LHCConcerns.com will pay $500.00 US to the best proposal that can reasonably prove 5% or less Risk of Planetary destruction from Micro Black Holes.
ReplyDeleteThe contest will conclude in a vote by site visitors on all reasonable proofs received, all proofs will be published and the contest will end not sooner than May 20th.
(LHCConcerns will make the final call on best proposal that reasonably proves 5% or lower risk from micro black holes being created by the Large Hadron Collider).
You may prove that ANY ONE of the following or provide any other reasonable Proof or method to prevent Micro Black Holes from being created by the Large Hadron Collider or prove that they are harmless!
1. The Large Hadron Collider will not make micro black holes.
2. Micro black holes created will be sent safely into space.
3. Micro black holes will evaporate.
4. Micro black holes will take more than 2 billion years to accrete the Earth. (If you can only prove a lesser time frame, then the prize will be reduced proportionately...)
5. Any form of cosmic ray argument that proves 5% risk or lower.
6. Find a way to make the Large Hadron Collider safe from creating micro black holes (we already requested different speed collissions or different mass collisions, LSAG told us it was not possible, they already thought of it).
It is harder than it looks, the LHC Safety Assessment Group (LSAG) could not produce a safety report...
(CERN and LSAG are still using the 1999 RHIC safety report that does not even address what might happen if micro black holes were created, because they did not know that it was possible at that time. We are also being generous on the 2 billion years, we want to be reasonable)
JTankers
LHCConcerns.com
Hi JTankers,
ReplyDeleteYour comment is completely ridiculous. I hope you are aware that with this 'argumentation' you are very efficiently undermining your own credibility. You have not brought up a single scientific argument. All you do is quote other people, and you have already demonstrated your lack of basic knowledge about the topic you are discussing.
Are you telling me that the Earth is safe because you believe that Professor Hawking has proven that micro black holes evaporate. Is that what you are saying?
I never said that. I believe the earth is save because I read Hawkings papers, did the calculation, read numerous other works on the topic (I recommend Birrell+Davies), did the calculations. Asked all the questions you too seem to have (e.g. the one about the negative energies), and convinced myself these derivations are physically and mathematically sound. I also did the calculations for the case of higher dimensional black holes, I read dozens of publications on the topic, I wrote my master's thesis on the Hawking effect, and my dissertation on the properties of mini-black holes.
Are you telling me that you have not read the rigorous peer reviewed studies that found no basis in science to support such conclusions?
I certainly missed one or the other publication on the topic. As I wrote in the text above I read the publications by Helfer that have been referred to, and that you too are referring to in the first quote. It seems to be pretty much pointless in discussing with you the details of this work given that I have the impression you don't know very much about the Hawking effect, but as I mentioned above, Helfer wrote himself explicitly "[These results] do not, as emphasized above, mean that black holes do not radiate [...]"
As to your second reference, this is about astrophysical black holes of very large masses so I do not know exactly what your argument is. Anyway, the full context to that sentence you cropped from that website is
"The results indicate that on average, "low mass" black holes of less than a hundred million solar masses are still growing at a significant rate. The team also measured the star formation in nearby low mass bulges and deduced that rate at which new stars form in these systems is a thousand times larger than the rate at which their black holes are growing. This factor of a thousand is in gratifying agreement with the ratio between bulge and black hole mass observed in inactive galaxies!"
The third reference by Don Page is a great paper! In fact, I recommend you read it. I already said above it is correct that we don't know quantum gravity.
The fourth 'reference' is a joke, right?
The fifth reference is by the same person as the first. If you had read this paper you'd have noticed that almost all of the 80 pages is a very nice summary of other people's research. There is no calculation supporting the claim you are making that black holes do not evaporate. Neither is there a calculation in the later papers, in fact he states he can not compute anything.
I find it very interesting that you are so very critical about the idea of pair production in the Hawking effect, but are completely uncritical with the idea that particle pairs of arbitrarily high energy can be prodouced in the asymptotically flat region, as Helfer seems to claim. It is of course hard to say whether this is in disagreement with observation without an actual calculation.
Besides this 'Rept.Prog.Phys.' isn't exactly a high-impact journal. I doubt it was the first journal this paper was sent to which means it was likely rejected in peer review several times (but this is just a speculation)
Okay, so where are the many thoroughly peer reviewed publications disputing Hawking radiation?
Best,
B.
BTW, just for completeness, the preprint of Rössler is here:
ReplyDelete"Abraham-Solution to Schwarzschild Metric Implies That CERN Miniblack Holes Pose a Planetary Risk."
He has also written A Petition to CERN, Honey, I shrunk the earth!
He has presented these ideas on a congess called "transmediale 08 - CONSPIRE...", as a keynote with the title The Paradox of the Big Bang: Reducing Fear by Accelerating Danger. Maybe he is just making a big joke.
Cheers, Stefan
Ah, Rössler with ö, and he's a chemist not a physicists, that's why googling Rossler physics doesn't give anything useful. Here is what Wikipedia says
ReplyDeleteOtto E. Rössler (born 20 May 1940) is a German biochemist.
Rössler was born in Berlin. At the age of 17, he became an amateur radio operator (DR 9KF). After considering becoming a monk, Rössler chose to major in medicine, with a specialty in immunology, for ethical reasons.
He was awarded his MD in 1966. Rössler then began his post doc at the Max Planck Institute for Behavioral Psychology, in Bavaria. In 1969, he started a visiting appointment at the Center for Theoretical Biology at SUNY-Buffalo. Later that year, he became Professor for Theoretical Biochemistry at the University of Tübingen. In 1976, he became a tenured University Docent. In 1994, he became Professor of Chemistry by decree.
The pdf you linked to above is actually two papers. Regarding the questions whether it's a joke, read the last two paragraphs (on page 6). He ends his acknowledgements with the sentence "Paper submitted simultaneously to Science, Nature and Z. Naturforsch. to get the best criticism of the world, with the publishing rights going to the one who accepts first."
Anything to add?
Hi Bee and Stefan:
ReplyDeleteThanks for the link to Roessler's petition. I hadn't seen it before, though I was aware of his paper estimating as little as 5 years for earth accretion by an accreting black hole.
I believe the problem that most people have with Hawking's idea is that, generally, there would be three different possibilities for a black hole sitting in the vacuum of space.
First, of course, under Einsteinian theory, it would simply just sit there, unchanging, unless matter were to come nearby and fall into it. That was the original theory, of course, before Hawking began talking about 'quantum effects' at the 'event horizon'.
We of course make particles and antiparticles every day. In our nuclear medicine departments, every day [including today] we slam protons into O-18 to make F-18, a positron emitter. When the F-18 decays [fairly rapidly because of its short half-life, which means we need to actually make it several times per day in some of our facilities], the nucleus loses a little bit of its mass, which is converted into the mass of a positron [and a neutrino], as well as their kinetic energies. This is then quickly converted back into energy, as the positron only travels about 1 millimeter before it encounters and electron, annihilating with two opposite-momentum photons of about 511 KeV each.
We also routinely make antiprotons by slamming high-kinetic energy protons into targets, creating lots of particles and antiparticles, some of which are antiprotons, which we then magnetically separate, store, and later collide with protons [as at Fermilab].
We always need to inject energy, however, to make such particles.
Hawking believes that the energy of the black-hole, however, can provide the mass for particle creation. While the idea is interesting, it is entirely different than what we do in the laboratory.
To sum up his idea, he envisions that a particle and antiparticle form at the event-horizon as virtual particles. When one falls into the black hole, the other wanders away, and now isolated, required to become real. Consequently, the other that fell into the black hole is required to reduce the mass of the black hole [to conserve total mass], being the equivalent of having 'negative mass'. That is the other odd thing about his idea.
It could be just as easily argued that a black hole would accrete a positive mass particle, requiring a nearby antiparticle to disappear.
However, in the vacuum of space, there would be no nearby particles, and such scenario would likely be suppressed, just as Electron-Capture radioactive decay is altered or suppressed if the nearby electrons take a different chemical configuration, or are absent [preventing the decay].
Regards,
Walter L. Wagner
Dear Dr. Wagner,
ReplyDeletethank you very much for your comment, and the nice explanation of positron emission tomography.
However, with respect to your discussion of the Hawking effect, maybe you read carefully again Sabine's replies to JTanker, especially the paragraph "Your 'explanation' why Hawking radiaton can't work ..." ?
Moreover, I strongly suggest that whoever on this blog starts again to discuss the Hawking effect on the basis of the hand-waving "antiparticle falls into the horizon" argument will be banned forever, for inflicting insufferable mental pain on the host, Sabine.
Thanks, Stefan
Stefan:
ReplyDeleteThanks for your response. I did as you suggested and read again from Jtankers, from which I quote Bee's response thereto:
"The brief explanation to your problem is the energy of the infalling particle is negative as measured by the observer at infinity because inside the horizon the time- and spacelike coordinates are exchanged so the energy has a sign change. This does not mean these particles anti-gravitate."
That is the problem that some physicists have - namely that "the energy of the infalling particle is negative".
While that does add up to zero net energy change [negative energy for the infalling particle, positive energy for the "Hawking Radiation" particle], thereby preserving the fundamental law that matter/energy is neither created nor destroyed, just changed in form, it poses a significant challenge to physics.
While the concept mathematically might be correct, in physics there is no demonstrated valid concept of "negative energy". This is a cute concept that is contrived to allow creation of a real particle/antiparticle ["Hawking Radiation"] without violating the law of the conservation of mass/energy.
While I am not asserting that it has to be wrong, it simply does not seem to be provable to be true.
It seems that it might also be true that a black hole might simply have a particle/antiparticle that is one of two newly-created virtual particles at the event-horizon fall into the black hole, thereby requiring any nearby particle/antiparticle to instantly vanish [without having to move through space to the blackhole], in order to preserve the total mass/energy of the system. This alternative explanation indeed seems even more plausible than Hawking's idea, though personally, if I were a betting man, I'd bet that neither occurs, and the black hole simply sits there unchanging until some stray matter falls into it.
Regards,
Walter L. Wagner
Dear Dr. Wagner,
ReplyDeleteThat is the problem that some physicists have - namely that "the energy of the infalling particle is negative" [...] While the concept mathematically might be correct, in physics there is no demonstrated valid concept of "negative energy". This is a cute concept that is contrived to allow creation of a real particle/antiparticle ["Hawking Radiation"] without violating the law of the conservation of mass/energy.
Are you saying you are suing CERN because you think Hawking evaporation requires particles of negative energies?
Who are the 'some physicists' that allegedly have this problem? Would you be so kind to point me to a publication?
Best,
B.
Perhaps I can answer the Doctor's question: Dirac's equations (which will not fit in a comment) lead to values of energy E that are positive or negative. The negative solutions are considered positive states of antimatter. Dirac's equations lead to prediction of the positron.
ReplyDeleteJust to be remindful, positrons have positive mass, antiprotons have positive mass, antineutrons have positive mass, etc.
ReplyDeleteIt takes real [positive] energy to create those real particles in a laboratory setting.
Regards,
Walter L. Wagner
Could you please explain to everyone reading this what happened in March of 2005 at the RHIC. Could you please explain what you think happened to the thousands of atoms that were not accounted for?
ReplyDeleteDo you think it is possible that the mass is still growing? If not, then why?
"A bosenova is a very small, supernova-like explosion, which can be induced in a Bose–Einstein condensate (BEC) by changing the magnetic field in which the BEC is located, so that the BEC quantum wavefunction's self-interaction becomes attractive.
In the particular experiment when a bosenova was first detected, this procedure caused the BEC to implode and shrink beyond detection, and then suddenly explode. In this explosion, about half of the atoms in the condensate seem to have disappeared from the experiment altogether, remaining undetected either in the cold particle remnants or in the expanding gas cloud produced.
Under current quantum theory, this characteristic of Bose–Einstein condensate remains unexplained, because the energy state of an atom near absolute zero appears to be insufficient to cause the observed implosion."
March 2005 http://news.bbc.co.uk/1/hi/sci/tech/4357613.stm (Poor article fails to mention thousands of missing atoms and instead assumes radiation, there were missing atoms that may have clumped, not radiation that would have been detected.)
http://en.wikipedia.org/wiki/Bose_einstein_condensate#Unusual_characteristics
http://news.bbc.co.uk/1/hi/sci/tech/4357613.stm
http://arxiv.org/PS_cache/hep-th/pdf/0501/0501068v3.pdf We argue that the fireball observed at RHIC is (the analog of) a
dual black hole.
http://en.wikipedia.org/wiki/Bosenova
In the particular experiment when a bosenova was first detected, this procedure caused the BEC to implode and shrink beyond detection, and then suddenly explode. In this explosion, about half of the atoms in the condensate seem to have disappeared from the experiment altogether, remaining undetected either in the cold particle remnants or in the expanding gas cloud produced.
JTankers,
ReplyDeleteIn case you haven't noticed this post is about black holes at the LHC. From your sudden change of topic I assume you have nothing to reply to what I said above. For your other confusions, please consult somebody else, my time is finite.
Best,
B.
PS: You might want to clarify the words 'fireball' and 'dual black hole' before you make a complete fool out of yourself.
Hi Louise, Thanks for your help :-)
ReplyDeleteDear Dr. Wagner,
ReplyDeleteJust to be remindful, positrons have positive mass, antiprotons have positive mass, antineutrons have positive mass, etc.
Correct. So what is your problem then? It's a tunnel effect. Particle out with positive mass, leaves behind missing positive mass. (I am not sure what Lousie was trying to say above.) Recommended reading: Parikh and Wilczek: Hawking Radiation as Tunneling. As mentioned above, I explained previously why I dislike the explanation with the particle pairs at the horizon. If you're to inflexible to rethink, maybe ask yourself where usually the energy for particle production in a strong background field comes from. Hint: it doesn't happen without the background field.
Could you do me a favor and answer my question: Are you suing CERN because you think Hawking evaporation requires particles of negative mass?
Best,
B.
B. writes: "PS: You might want to clarify the words 'fireball' and 'dual black hole' before you make a complete fool out of yourself."
ReplyDeleteThose are not my words, they are the words used in the peer reviewed study posted on http://arxiv.org/PS_cache/hep-th/pdf/0501/0501068v3.pdf.
The title is "The RHIC fireball as a dual black hole" by Horatiu Nastase of Brown University. Dated March 22, 2006.
It is clear you have not read the peer reviewed study of this incident. Please also research the thousands of missing atoms, the wikipedia article on Bose-Einstein condensate is a great starting point. I can also point you to the Nobel laureate on the team if you need assistance.
Hi JTankers,
ReplyDeleteCongratulations. You've ignored my advice and made a fool out of yourself. I read somewhat more than the title of that paper, and I also know what they are talking about. I am not presently in the mood to talk about Bose-Einstein Condensation, please excuse me, but I've got a paper to write. Best,
B.
Hi Bee:
ReplyDeleteIt looks like we both have people jumping to our respective 'sides' with less-than-correct explanations. C'est la vie.
Yes, I have also read that "Hawking radiation" can be equated to a particle or anti-particle quantum-tunneling beyond the 'event horizon'. I don't believe that explanation either is absolutely required. Perhaps it's possible, perhaps not.
It gets back down to the fundamental difference between our creation of real particles/antiparticles in the laboratory [with the input of energy equivalent to the rest-mass of both], and the supposed ability to do so at the event-horizon of a black hole without input of energy; but instead by 'quantum-tunneling' of some of the mass of the black hole to a point outside of the event-horizon as a new particle.
By the very original definition of the 'event horizon', such is forbidden. Hawking was looking for a way to account for the lack of primordial black holes, and came up with his idea that they "evaporated".
Occam's razor, however, would suggest instead that they simply never existed, or that if they exist they haven't been detected, and that particles cannot "quantum tunnel" outside of the event horizon.
It doesn't matter whether you look at Hawking's idea as either a positive-mass/negative-mass explanation [as you originally indicated when speaking about an "observer at infinity" seeing the infalling particle as having "negative mass"], as I've frequently read; or whether you look at it as "quantum tunneling", an explanation I've also read. Either way, it simply is not proof of Hawking's idea, and as you know, in physics, we always look for the simplest explanation.
Until Hawking radiation has been observed [which might happen with our GLAST satellite and other planned gamma observatories], the simplest explanation is that it does not exist, thus not requiring us to entertain novel physics. Of course, that is not proof that Hawking's idea is wrong, either. Lots of novel ideas are out there awaiting proof.
Why don't you do this.
I believe you live somewhere in Germany, though I'm not certain where. Nearby you will find lots of hospitals, including University hospitals. The larger ones will have larger nuclear medicine departments.
Why don't you visit one of those nuclear medicine departments, and see what we do. If they have a medical cyclotron, you'll feel right at home.
Check out the patient load, and how we train our nurses in proper shielding techniques for the 511 KeV gammas [very penetrating], including syringe-shields, etc., as well as the personnel dosimetry, including finger-ring and whole body.
See if they have a Moly generator of Tc-99m. Check the DU shielding we use to protect the radiopharmacists. If they do have a Moly cow, it is almost certainly not irradiated with the Canadian reactor used in North America, but from the one in Holland.
Indeed, you might even find yourself desiring to become part of the team.
And if you send me your email, I'll send you the copy of the Complaint and its seven supporting Affidavits that will give you a clearer understanding of the lawsuit. Send it to lhcdefense@hotmail.com
Best regards,
Walter
I propose to just rename that "black hole" thingy that improbably may exist for some finite time a "mixer". Particles go into its creation and different particles comes out again really, really fast. This will keep bad mental associations by problem people in check. Amazing what people get worried about. Expect Michael Crichton to issue another sucky book during summer to cash in before the LHC goes live. If stable light black holes were that easy to produce, it will probably have a few embedded ones (with charge so they are disguised as electrons?)
ReplyDelete"Fine, at least prove the risk is less than 5%, then I can sleep at night believing my children may have some chance of growing old."
WTF? Why not worry about the 50'000 nukes lying around or McCain getting elected or traffic accidents or major body malfunctions? You cannot "prove" risks anyway.
I will get my coat. It's the one with the Black Mesa Research Facility logo on the back.
Dear Dr. Wagner,
ReplyDeletethe Frankfurt physics department had/has good connections to Siemens Medical Solutions in Erlangen, and we did once a guided tour of the factory where they assemble their NMR and PET scanners. And at the GSI in Darmstadt, we could see the heavy ion accelerator and beam lines explored there to irradiate tumors - a dedicated machine for clinical use with carbon ions went online at the Radiological Clinic Heidelberg earlier this year. Nuclear physics has really many great applications in medicine which often may not be appreciated. Of course, proper radiation protection is extremely important.
But to get back on-topic: Since Hawking radiation is a very robust prediction and natural consequence of dealing with quantum field theories on a curved background metric, arguing it away by reference to Occam's rasor doesn't make sense to me - you would have to get rid of either QFT or GR.
It's true, particle (pair) production in strong background fields, with the necessary energy extracted from the field, hasn't been observed for the gravitational or the electromagnetic case (resulting in Hawking radiation or the "sparking vacuum", respectively) because the conditions necessary to see the effect could not be produced yet under laboratory conditions. But for the strong force, the corresponding idea, the "decay of the hadronic string", yields a well-tested explanation for particle production in proton-proton and nucleus-nucleus collisions.
Best regards, Stefan
Hi Walter,
ReplyDeleteThere are always different possibilities to interpret calculations, some are more, some are less useful. As I said, I always disliked the interpretation with the particle pairs at the horizon.
a positive-mass/negative-mass explanation [as you originally indicated when speaking about an "observer at infinity" seeing the infalling particle as having "negative mass"],
Notice that I carefully spoke about what the 'observer at infinity sees as', and not about a 'real' particle that is produced as you suggested.
Until Hawking radiation has been observed [which might happen with our GLAST satellite and other planned gamma observatories], the simplest explanation is that it does not exist, thus not requiring us to entertain novel physics.
The simplest explanation is not always that something just doesn't exist. Here, it is certainly simpler if Hawking radiation is as predicted, as has been derived using various different approaches. It does, as I explained in my post, not require novel physics. It is based on quantum field theory and classical gravity. The fact that there is no serious alternative explanation in which there is no Hawking radiation should make it very clear that the difficulty is in talking it away. I agree that we do not know something exists until we have measured it.
I also want to comment on something that came up in what JTanker said above. The idea that theoretical physicists would tend to conformity and hesitate to disagree, and thus backup established results is completely ridiculous. If I had a colleague who thought he had disproved Hawking's result and could show that black holes do not evaporate, do you really believe he would leave such a proof in his drawer?? Gee, no, he would send it to Science and Nature and become famous as the-guy-who-proved-Hawking-wrong.
(I don't know how good your German is, but Stefan informs me Rössler apparently wants to hold a let's-prove-Hawking-wrong conference. And that would probably be fun indeed. Nothing more boring than a conference where everybody agrees on everything. That doesn't make his claim any more credible though.)
Anyway. I live in Canada, Stefan lives in Germany. I am not tremendously interested neither in visiting the next hospital nor in reading your lawsuit.
Best,
B.
Hello B.
ReplyDeleteI would like to know that before micro black holes may be created at a rate of up to 1 per second, that a rigorously peer reviewed safety study will be published in reputable physics journals and appropriate time will be given for reasonable peer review based on the possible consequences to the entire current and future populations of Earth.
I read the 1999 RHIC safety study, and it did not contain any statements as to the safety of actually creating micro black holes on Earth. It did not address issues of micro black hole stability, it did not address Hawking Radiation, it did not address capture rates by Earth's gravity and it did not address Earth accretion times.
Will this be done before collisions begin at the Large Hadron Collider, currently predicted for as soon as Mid-August 2008?
Thank you,
JTankers
LHCConcerns.com
Hello Bee and Stefan:
ReplyDeleteThank you for your comments.
Yes, Siemens is a giant in medical physics. I'm hoping they'll be working with me/us in the near future on a replacement for the century-old technology of X-rays.
As you know, our most sophisticated medical imaging technology [CT imagers, etc.] generates photon beams [i.e. X-rays] by the same technique discovered by Roentgen more than a century ago - slamming high-E electrons into a target, kicking out the innermost electrons from their orbitals, and having the outer-orbital electrons cascade on down, giving both characteristic "X-ray" [K, L, etc. shell] as well as brehmstrahlung radiation, with thus a huge spread in frequencies of the photons. We try to 'clean it up' with 'filters', which only eliminate the lower-E photons.
A few years ago, some of my associates came up with a different technique entirely, which has been demonstrated on a bench-top apparatus as valid. It uses a phenomena that was also discovered about a century ago, namely Compton scattering.
A high-E beam of electrons of about 30 MeV is aimed towards a laser. The laser aims a beam of low-E [a few eV, in the visible light frequencies] photons at the electron-beam, hitting the electrons nearly head-on, and they are Compton back-scattered at about 30 KeV, being a type of "X-ray", or at least in the X-ray range of photon energies.
What is nice about this is that the photons will be a discrete single energy, rather than a broad spread of energies, due to the discrete energies of the laser and of the e-beam.
What is even nicer is that the photon energies can be changed to any desired frequency simply by changing the energy of the e-beam! I.e., you can dial in the desired energy of the "X-ray" beam.
So, if you want to image Iodine in the body, then just dial the photons to the K-shell of iodine [about 27 KeV, as I recall], and presto, you have an "X-ray" beam that will be preferentially absorbed by iodine, which thus becomes an 'opaquing' agent. The reduction in radiation exposure to the patient would be tremendous [about 1,000 fold by the inventor's calculations], and it opens up the possibilities for tremendous new techniques.
Anyway, I did want to thank you for providing me with the link to Otto Roessler's most recent interview. I believe his comments are quite thoughtful.
Ich wohnte einst in Oesterreich fuer ein paar Monaten wann ich war noch ein Kind [16], und kann noch ein wenig auf Deutsch reden. Ich glaube dass Sie, Bee, war nicht hier zu Erde wann Ich lernte Deutsch und sprach auf Deutsch im Tirol.
How do you guys work a marriage with one in Germany, one in Canada? [You don't need to answer a personal question like that - just curious].
Best regards,
Walter L. Wagner
P.S. I believe Jtankers last comment is also quite appropriate, even if he doesn't have as in-depth of a knowledge of physics as others.
Dear Mr. Tankersley,
ReplyDeleteindeed, the 1999 report prepared for RHIC does not deal with the speculative micro black holes which now create all this confusion - the ideas by Arkani-Hamed and others about large extra dimensons on which all this is based only came up around the same time.
As mentioned in the NYT article you may have read, there is a paper in preparation by Michelangelo Mangano and Steve Giddings dealing at length with the potential risk. To my knowledge, this paper is currently under peer review.
Dear Dr. Wagner,
thank you for explaining this method using the Compton effect for the creation of narrow-band X rays for medical purposes - sounds interesting.
Best regards, Stefan
Here's the CERN report from 2003.
ReplyDeleteHi Walter,
ReplyDeleteYes, this is really fascinating. I've been very intrigued by MRI during my undergrad studies and indeed considered specializing in this direction for medical applications.
However, to summarize the impression I got from this exchange: your knowledge about the theoretical background of the Hawking effect is rather incomplete, and your judgement seems to be based on a feeling of uneasiness due to lack of understanding. It is true that we have no experimental proof the earth is completely safe, but one could make the same claim each time an experiment is made for the first time. Each time a genetic modification is made there is the possibility it will erase mankind, and possibly one day somebody composes a song that triggers a short circuit in the human brain and leads everybody who hears it to commit suicide. Yet these possibilities are according to the expectations our present knowledge allows us to have completely ridiculous. Black holes eating the earth ranks on a level of equal plausibility.
Sadly, a catastrophe scenario with black holes make a good topic in the media because the term has long reached the mainstream and is attached to scary objects.
Reg JTankers last comment: I have to admit that our community was slow to notice the momentum this topic gathered, and slow to publicize the reasons why the scenario is extremely implausible. However, I find it very irresponsible to scare the average person on the street with doomsday scenarios, this is completely unnecessary.
Please don't misunderstand me: I am usually very happy when the research we do attracts attention, and when people ask questions. In the case of JTankers however, it is completely obvious that there is absolutely no desire to actually learn something, but just to copy-and-paste vacuous accusations from one website to the next. Anyway, thanks for dropping in.
Best,
B.
PS: Since you asked - in case you're interested in my CV, here is an extended recent summary.
Hi JTankers,
ReplyDeleteI was about to say the same as Stefan. We've heard there is a paper presently in peer review that hopefully will set an end to this discussion. As I said in reply to Wagner's comment above, I admit that our community was probably slow to realize the attention this topic received in the media. When the idea with the micro-black-holes came up, all of us who started working on the topic (at least those that I know), made these estimates, and we convinced ourselves that the orders of magnitude we were talking about would not allow the world to end any time soon. Yet, estimates of that form don't usually make it into peer reviewed publications, they are too obvious.
However, I guess you are not following our blog too closely, so maybe let me mention that I regard this development as part of a larger problem that is the changing interaction between the scientific community and the broader public. It is an exchange that has become increasingly important during the last decade and even fundamental research as well as the scientists themselves now receive more attention than used to be the case. On the side of the scientists there is still a lot to learn in this regard. Some aspects of this I wrote about in my post Fact or Fiction. I sincerely hope that such scary stories that seem to be mostly based on lacking understanding and missing explanations in the pop science arena will become avoidable once we've gotten used to the audience we have having increased considerably and that we have to be very careful with not causing unintended misconceptions because we believe some things are obvious.
Best,
B.
Hello Bee,
ReplyDeleteI agree, that we have no experimental proof the Earth is completely safe, but of course nothing is "completely" safe.
What I would like is reasonable proof that the Earth will be reasonably safe from creation and capture of micro black holes.
I am pleased by the statement: "We've heard there is a paper presently in peer review that hopefully will set an end to this discussion."
Until this document is released and independently peer reviewed by the larger scientific community, could you please refer me to the best peer reviewed studies that have been rigorously, openly and independently peer reviewed that would tend to indicate no reasonable risk over the reasonable life expectancy of Earth from creation of micro black holes and capture by Earth's gravity.
Mein Deutsch ist nicht so gut, (dies ist übersetzt von iGoogle), aber ich lebte in Deutschland seit etwa 3 Jahren, beginnend als Tank Platoon Leader. Mainz-Wiesbauden Bereich. Ski in Österreich ... Many years ago, during the time of the fall of the Berlin wall...
Thank you,
James Tankersley Jr.
Am I the only one here who thinks it would be incredibly cool if the earth was swallowed by a black hole generated by the LHC (however unlikely that would be)? Would we be, like, instantly sucked into it or would we be, like, dragged out of our rooms and down the road to Switzerland? How cool would that be, to see all the world sucked in. I hear the LHC will not have enough power to create a dangerous black hole, in which case may I suggest the "up" the power to make it more likely.
ReplyDeleteHi Bee:
ReplyDeleteI read through your "CV", but can't quite figure out how you ended up in Canada with Stefan in Germany. It does not compute.
My own "CV" is somewhat mundane as well. After several years in theoretical and applied experimental physics at Cal in the mid 1970s, I began working on pragmatic physics problems for the US Government - such as how to reduce the number of nuclear war-heads then in the arsenals of the US and the then USSR, etc. Since Germany doesn't have those kinds of headaches [or, at least, it's not supposed to!], you likely can't imagine what it's like to work in nuclear safety/security when there are some 30,000 nuclear bombs aimed at you, sitting atop ICBMs, with launch codes already programmed into the computers with hundreds of US cities [and USSR cities, too] as the target coordinates, with a 10-minute margin of error as to lanunch/not launch. Not an easy task.
Fortunately, some of the programs on which I was working, aimed at converting the warheads into nuclear reactor fuel, seemed to make some progress. It is, however, a continuing process.
Contrary to your misconceptions, I have read quite a few theoretical versions of Hawking's idea. As I indicated, I believe that Hawking's idea could be possible, but there is no compelling reason to believe it must be so.
Indeed, as I mentioned before, I believe it might very well be the case that any particles that might be near to the event-horizon [e.g. 1 Angstrom away or thereabouts] could readily quantum-tunnel into the black hole. This seems a far more plausible idea than that a 'particle' within the black hole would 'quantum tunnel' out of the black hole. Tunnelling into the black-hole would produce a lower overall ground-state, it would seem, and should thus be the favored reaction. Indeed, I believe this would make the topic of an excellent paper on that possibility, and I would suggest you might find it of interest. You might just be doing humanity a favor.
Frank Wilczek wrote about black hole evaporation from the "negative energy" perspective you first mentioned as follows:
"…there exist freely propagating negative energy modes inside the horizon which cause the black hole to shrink. As a consequence, the black hole's radius decreases and the external volume of space, over which one integrates the field, increases. This, kinematically, is why the radiation process is allowed." [http://www.nature.com/nature/journal/v435/n7039/full/435152a.html]
This, kinematically, relies upon a BS concept of "negative energy". It's nice to know he believes he understands what's going on inside of a black hole.
Anyway, I believe we would all be far better off if we placed a moratorium on operation of the LHC while these issues are thoroughly addressed [and not just by the few of us doing so presently, with nothing resolved; particularly when the proponents put forth such drivel in other areas of physics such as the "cosmic ray argument" that's now been debunked]. In the interim, there is much work left to be done in many many fields of physics.
The "tunable monochrome X-ray" [as the inventor calls it] is but one such area of interest. Since there are literally billions of dollars [or Euros] worth of conventional X-ray equipment out there, the market is tremendous.
There are literally hundreds of other worthy projects in the works. Have you heard about the new neutron spallation apparatus nearing completion at Oak Ridge?
Here on the Big Island we're trying to get the Thirty Meter Telescope built, which would be an excellent adjunct to our already World-Class telescope community.
And, of course, there is always the old stand-by of the ITER.
Finally, you should be careful when comparing the probabilities of something going wrong. I've heard ludicrous comments from physicists that 'shaving' might cause the end of the world, or that the LHC might create 'dragons', as being of the same likelihood that Hawking Radiation won't work. That's why I know at least one knowedgeable laywoman refer to such people as "scientist-bookies" because they pull their 'odds' out of thin air without a shred of calculation to substantiate what they say.
And then we have these weirdo voyeurs who actively proclaim they want to see the Earth devoured being in your camp?!. What do you make of that?
Regards,
Walter
-----------
Hi Walter,
ReplyDeleteI believe it might very well be the case that any particles that might be near to the event-horizon [e.g. 1 Angstrom away or thereabouts] could readily quantum-tunnel into the black hole. This seems a far more plausible idea than that a 'particle' within the black hole would 'quantum tunnel' out of the black hole. Tunnelling into the black-hole would produce a lower overall ground-state, it would seem, and should thus be the favored reaction.
This is complete nonsense. Particles don't need to tunnel into black holes, they can just fall in. The only way you could lower the energy outside (which starts with vacuum) is to have a flow of negative energy states to plus infinity, which, as you seem to know, is also nonsense. If you could lower the outside groundstate below zero it would mean our vacuum isn't stable, but to me it looks pretty much as if it is.
Indeed, I believe this would make the topic of an excellent paper on that possibility, and I would suggest you might find it of interest.
If you believe this would make a topic for an excellent paper, why don't you write it, put it on the arxiv and try to get it published?
You might just be doing humanity a favor
You might just be doing humanity a favor if you'd stop scaring people unnecessarily. If you really think you can prove there is a flaw in Hawking's conclusion you should write a paper, and not sue CERN because you want people to listen to you.
I read through your "CV", but can't quite figure out how you ended up in Canada with Stefan in Germany. It does not compute.
No, my life doesn't compute, sorry. The short summary is I went to the USA and later to Canada to find a place I'd fit in, but I still haven't found one.
And then we have these weirdo voyeurs who actively proclaim they want to see the Earth devoured being in your camp?!. What do you make of that?
I don't take that comment seriously.
Finally, you should be careful when comparing the probabilities of something going wrong.
You should be careful with your reading. I didn't talk about probabilities or likelihoods anywhere.
Best,
B.
Hi James,
ReplyDeleteIt is not actually clear to me what you are asking for. Estimating risks isn't a field I work in, neither do I know anybody who does. Safety considerations for experiments isn't something that gets usually published in scientific journals, just go to the website of any journal and read through their blurb. The proposals for experiments, especially for constructions as large at the LHC, go through a huge number of peer reviews on various stages, and - so I would think - through various legal checks. If you don't like this process to not be public, I'm not the one to complain to.
What I would like is reasonable proof that the Earth will be reasonably safe from creation and capture of micro black holes.
As far as I am concerned there is no 'reasonable' risk black holes grow because there is no 'reasonable' theory in which black holes do not evaporate. As long as there is no consistent theory that predicts black holes remain stable once produced, this possibility remains unreasonable.
Best,
B.
Hello Bee,
ReplyDeleteIt is not actually clear to me what you are asking for.
What would be a good start would be links to the best independently peer reviewed study that supports the following, preferably to a degree of certainty appropriate to the potential threat.
1. Reasonable proof or best thesis that Hawking Radiation will cause micro black holes to decay.
2. Reasonable proof or best thesis that growth rates of stable micro black holes would be so slow as to not pose a reasonable threat to Earth during Earth's reasonably expected life span.
Thank you,
James Tankersley Jr.
Hi James,
ReplyDeleteIt is not clear to me what you are asking for because nobody can proof anything about the future. Since every paper published in a scientific journal is peer reviewed (I do not know what you mean with 'independent' - independent of whom or what), there are thousands of papers for both points you are asking for, and I am sure you know how to find them on SPIRES or the arxiv. If not, you can start with the references in our post Micro black holes, and the references in the references and so on and so forth. Scientists are careful people, you will not find them claim anything of what they say is a 'proof', it is usually called a 'prediction' that is based on the assumptions stated in their work.
It doesn't seem to be quite clear to you that the argument to support claims is missing on your side, not on ours. In case this still isn't obvious: Hawking's original papers show black holes evaporate. There is no serious and consistent argument invalidating this calculation, which means it is according to our best present knowledge correct, and this is supported by 30 years and thousands of follow-up works.
If you claim these calculations are wrong, you are the one who has something to proof.
Best,
B.
Hello Bee,
ReplyDeleteIn response to: Hawking's original papers show black holes evaporate. There is no serious and consistent argument invalidating this calculation
Do you consider Dr. Adam D. Helfer’s thesis: "Do black holes radiate?, 2003" http://arxiv.org/PS_cache/gr-qc/
pdf/0304/0304042v1.pdf and
"Quantum Nature of Black Holes, 2005"
http://arxiv.org/PS_cache/gr-qc/
pdf/0503/0503052v1.pdf to be non-serious and non-consistent? (Dr. Adam D. Helfer http://www.math.missouri.edu/
personnel/faculty/helfera.html).
In “Do black holes radiate?, 2003”, Dr. Helfer writes “…no compelling
theoretical case for or against radiation by black holes…” and ”…assuming that black holes do radiate should be considered tentative, and the consequences of not making this assumption should be given comparable weight.”
In “Quantum Nature of Black Holes, 2005”, Dr. Helfer writes “taking interactions between quantum fields into account completely alters the picture drawn by Hawking” and “[HR] assumes that interactions between the quantum fields may be neglected, even (or especially) as those energies exponentially increase” and "...it is acknowledged that there are as yet no very good responses to these concerns" and "...the correct picture of a black hole is very different. The black hole, far from being an essentially classical object with only minor quantum corrections, has a strong quantum character which profoundly affects physics in a region of space–time, a region extending beyond the hole a distance comparable to the size of the hole itself. In this region, not merely “virtual” vacuum fluctuations, but real Planck-scale physics must be prevalent."
Please refer me to the best credible refutation of the well known thesis above put forward by Dr. Adam D. Helfer.
Thank you,
James
Hello Bee:
ReplyDeleteI'm not quite certain what field of work you're looking for. Always lots of interesting work at our various telescops. Subaru, Gemini, Keck, etc. This might be a change from your original theoretical research interests. You'd learn lots, however, and it's a great place to live. Lots of Aloha.
The new neutron spallation source at Oak Ridge likely needs people. Google on it and find out. They're using a Bevatron accelerator, and liquid Mercury as the target. Because of the high flux of the neutrons, once the target region becomes operational, it will be sealed thereafter for the next 40 years, so everything must be done by remote control. I'm not certain, but I believe the flux is high enough to make Moly cows, giving us a good back-up for our reactor production.
As to my suggestion about particles tunneling into a black hole; yes, they can also fall in. However, I was thinking more along the lines of very small black holes in which the gravitational attraction is miniscule, and 'falling in' is not likely. In that sense, they'd 'tidy-up' nature by eliminating stray particles that came near and simply tunneled in.
I believe that Jtankers does have a point, even if you disagree with the conclusion or substance of the Helfer article. It was peer-reviewed and published, and he does call into question the necessity of requiring Hawking Radiation to be valid [as do I, of course].
If you're interested in visiting Hawaii [Big Island], I'd be more than happy to take a day off and show you around as a 'tour guide'. You'd enjoy the Volcano [currently erupting]. I could introduce you to some of the astronomy people. Who knows, a friend of mine who's interested in this issue might even be willing to fly you on out?!
Regards,
Walter
------------
Hi James,
ReplyDeleteDo you consider Dr. Adam D. Helfer’s thesis: "Do black holes radiate?, 2003" [...] to be non-serious and non-consistent?
It seems we have now made a full circle? I have to admit it is very frustrating for me to talk to somebody who apparently is neither willing nor able to listen to anything I say. And since you seem to be somewhat slow with understanding: I am talking about you. Hello, do you actually read what I write?
So we are now back to your attempt to back up your claims with references whose actual content seems to be of little relevance for you, you are just cropping a sentence here or there that sounds useful to you. I previously offered my opinion on Helfer's work, and I also commented on it in the text. Yes, the 80 pages thesis you are referring to contains a lot of claims, but no substantial calculation. Almost all of the 80 pages is a summary of other people's work, but for a thesis this is not surprising actually. It is actually a well written summary that is an interesting read, but either way, it does not contain any actual calculation invalidating Hawking's result.
Could you please summarize in your own words how you think Helfer shows that Hawking's calculation is wrong?
Also, as I repeatedly mentioned above, even if you would believe what Helfer says, he explicitly states "[These results] do not [...] mean that black holes do not radiate [...]" which is the claim that you are trying to make. So could you please tell me what exactly you think the content of your argument is?
Please refer me to the best credible refutation of the well known thesis above put forward by Dr. Adam D. Helfer.
I doubt this thesis qualifies as 'well known' in any possibly definition I can imagine for 'well known'. There is no refutation from the community because there is no argument in this thesis. It is in the very best case 'not even wrong', in the more likely case it is just simply wrong. I read it as well as the follow up works for rather obscure reasons, but it is of no surprise to me nobody of my colleagues wants to waste time with it. Helfer does not actually compute anything. Instead, he claims he can not compute anything.
It is a mystery to me how you can believe you are making a scientific argument with quoting sentences for which you have no derivation supporting them. Worse, from the level of the argumentation you are leading, I doubt you would be able to recognize a proof should it bite you in the ass. I have sincere doubt you even know what a Bogoliubov transformation or a Fock state is, so what are we talking about here?
It is pretty clear to everybody reading your comments that your repetition of quotations from publications by a Helfer is a pathetic attempt to give credibility to completely vacuous arguments.
Now here is a question for you. Could you please tell me your motivation for doing this? Why are you evidently not willing to listen to any explanation telling you your concerns do not have any scientific basis. Why aren't you actually looking into the derivation and why don't you try to understand the basis of these calculations? This whole exchange pretty much reminds me of religious convicts knocking at my door who will just repeat their mantra without even trying to have a rational conversation.
Best,
B.
Hi Walter,
ReplyDeleteI was recently in Oahu, nice, I will certainly visit some of the other islands at some point (should my finances allow it).
As to my suggestion about particles tunneling into a black hole; yes, they can also fall in. However, I was thinking more along the lines of very small black holes in which the gravitational attraction is miniscule, and 'falling in' is not likely. In that sense, they'd 'tidy-up' nature by eliminating stray particles that came near and simply tunneled in.
Unless you are talking about the angular momentum barrier for higher l-modes there is no potential wall for infalling particles in the black holes case. This is unlike the situation in nuclear fusion where two positively charged nuclei have to overcome a repulsive interaction. Either way, this does not give any more plausibility of your above claim since for the black hole to grow you would still need to emit negative energies to plus infinity which is not consistent because the vacuum in such a theory would be unstable. I honestly have no idea what you are trying to say, neither do I see how this invalidates Hawking's calculation. If you really want to follow this thought and argue black holes do not evaporate, I encourage you to write it down and put it on the arxiv. Suing CERN because you hold these opinions without at least having them discussed in the community is very inappropriate.
I believe that Jtankers does have a point, even if you disagree with the conclusion or substance of the Helfer article. It was peer-reviewed and published, and he does call into question the necessity of requiring Hawking Radiation to be valid [as do I, of course].
Saying 'it was peer reviewed' isn't something that I consider a scientific argument. We all know that peer review isn't perfect - nothing done by humans ever is. If you want anybody to take you seriously, you will have to explain how Helfer shows Hawking's calculation is wrong and you will have to make clear that it is a strong argument. Good luck. Start with reading the papers. Btw, I would suggest you decide on whether you believe what Helfer says or whether you believe black holes emit negative energies, because that doesn't quite seem to be in agreement with each other.
Best,
B.
Hi Bee,
ReplyDeleteI am not concerned about the safety of the LHC. I have seen plenty of reasons to say why it is safe. However, I'd like to get a second opinion on this comment. It was made in response to JTankers $500 offer:
If you go to your google browser and type "LSAG CERN", you get, as the very first link, the following presentation:
http://lhc2008.web.cern.ch/LHC2008/documents/LSAG.pdf
This is a presentation by Michelangelo Mangano of the LSAG. You can read through the arguments presented right there.
They are paying attention to the absolute worst case scenarios that you all have posited, and have concluded that there is no credible or reasonable threat.
Summary of Reasons:
1) If black holes are produced at the LHC in any meaningful way, in order to be stable, then quantum mechanics is incorrect. This is aside from the blackbody radiation from Hawking radiation. Therefore, for a black hole to be stable, both Hawking radiation must be false, and quantum mechanics must be false. The odds of this are very very low.
2) There is absolutely no guarantee of black hole production at CERN to begin with.
3) Even IF black holes are stable (i.e. quantum mechanics are incorrect and Hawking radiation is false... already extraordinarily unlikely), there is a study ongoing to deal explicitly with this absolute worst case scenario to allay your fears. The heart of the study relies on proving that microscopic black holes will be captured by neutron stars, and given the assumption that the LHC will produce them at all, one can predict the number of these things that would be flying around our neighborhood of the universe. Since neutron stars are very very very dense, they will attract any doomsday black holes. The preliminary results from this study show that the time that a neutron star would take to attract such a doomsday black hole is about 100 million years, which is less than the lifetimes of actual neutron stars observed. They will be finalizing their calculation and publishing their results, however at this point it is completely unreasonable to expect that the LHC will result in any credible danger to anyone.
I hope that you send the $500 to Michelangelo and the rest of the LSAG, maybe they can get some nice champagne for our collaborations to drink when the first beams collide in August or September.
This post sounds very solid to me, and if I'm not mistaken, this person works for CERN. This post was made by northofthenorthpole over at lhcconcerns.com.
Hello Bee,
ReplyDeleteIn response to: “I have to admit it is very frustrating for me to talk to somebody who apparently is neither willing nor able to listen to anything I say. And since you seem to be somewhat slow with understanding: I am talking about you. Hello, do you actually read what I write”
It is not my intent to frustrate you, I understand how difficult your job must be. My degree is in Computer Science and I only completed two semesters of Physics in college. But my IQ has been measured as at least 140 so problem solving and learning is not an issue.
Could you please summarize in your own words how you think Helfer shows that Hawking's calculation is wrong?
I am not qualified to defend Helfer’s work, but I can comprehend that he clearly states, and I quote “no compelling theoretical case for or against radiation by black holes “. I believe what he is concluding is at least 50% chance that Hawking Radiation could fail in his opinion.
“[Helfer’s thesis] does not contain any actual calculation invalidating Hawking's result”
My understanding is that Helfer’s work is scientific, rigorous and well respected by his peers in physics. And to my knowledge there is no rigorous refutation of Helfer’s work. I am not qualified to personally comment on the quality of Helfer’s work.
However, James Blogget who has a Masters Degree in Statistics conducted a Delphi study of 15 physicists and estimates that Hawking radiation would fail ranged from 0% to 50%. The data are as follows: 0, 0, 1E-10, 0.001, 0.01, 0.01, 0.01, 0.02, 0.02, 0.07, 0.1, 0.1, 0.3, 0.35, 0." (http://www.lhcconcerns.com/
#James_Blodgett)
The following physicists have published papers that question whether Hawking Radiation would work at all (links from http://www.risk-evaluation-forum.org/links.htm):
Adam D. Helfer, "Do black holes radiate?" Reports on Progress in Physics. Vol. 66 No. 6 (2003) pp. 943-1008.
Questions the existence of Hawking radiation. http://xxx.lanl.gov/abs/gr-qc/0304042
William G. Unruh and Ralf Schützhold, "On the Universality of the Hawking Effect," Physics Review D 71(2005) 024028. Considers plausible quantum gravity scenarios in which black holes radiate at rates very different from those proposed by Hawking, or do not radiate at all. http://arxiv.org/PS_cache/gr-qc/pdf/0408/0408009v2.pdf
V.A. Belinski, "On the existence of quantum evaporation of a black hole," Physics Letters A 209(1) (1995) pp. 13-20.
Asserts that Hawking radiation does not exist. http://www.ingentaconnect.com/content/els/
03759601/1995/00000209/00000001/art00785
The fate of the planet might rest on the validity of Hawking Radiation. Why do you dismiss the concerns of these physicist?
Cheers,
James
JTankers, I think it's funny you mention the Unruh article. I directly to this quote by William Unruh, from the New York Times:
ReplyDeleteBut William Unruh, of the University of British Columbia, whose paper exploring the limits of Dr. Hawking’s radiation process was referenced on Mr. Wagner’s Web site, said they had missed his point. “Maybe physics really is so weird as to not have black holes evaporate,” he said. “But it would really, really have to be weird.”
http://www.nytimes.com/2008/03/29/science/29collider.html?_r=1&pagewanted=2&oref=slogin
Dear Mr. Tankersley,
ReplyDeleteyour IQ may have been measured as at least 140 so problem solving and learning [may] not [be] an issue, but to be sincere, this is not at all obvious to me from your demonstration of critical thinking in this thread or in other blogs/forums.
If, as you are willing to concede,
I am not qualified to personally comment on the quality of Helfer’s work.
you can feel free of course just to dismiss the comment about Helfer's argument by a researcher who has been working on this stuff since nearly ten years (I am talking about Dr. Sabine Hossenfelder, currently at the Perimeter Institute), and to ignore an explicit statement by Adam Helfer that his work does "not mean that black holes do not radiate" - but why on Earth do you then believe the results of a statistical survey, by whom? - 15 physicists have been interviewd, ouuh, I am shocked, who has found them, and where? Are we going to decide this question by a majority vote?
You are profoundly insulting my intelligence, even if it may be inferior to yours.
So, you bring up again Helfer - I believe I vaguely remember that this point has been discussed sometime, somewhere - and you have dug out some new papers... Are you sure that you have understood Unruh and Schützhold? We have met Schützhold last week - I had not the impression that he says that there is no Hawking radiation... Belinski has also been mentioned before, if you bother to read.
Why do you think we are too stupid to note that your are pathetically recycling the same stale stuff again and again?
But please, tell me something else: If you are so convinced that the Earth has to be saved, and that you know the guys who have the arguments to back this position, why do you waste your time on this blog with two physicists who see no reason at all to take your argumentation serious?
Actually, don't tell me, and just contact these guys instead and enlist them on your cause. That's not so difficult: They all have web pages where you can find their email addresses:
Adam D. Helfer is at the Department of Mathematics, University of Missouri, Columbia, Missouri.
William Unruh is at the Department of Physics and Astronomy of the University of British Columbia, Vancouver, Canada.
Ralf Schützhold is at the Department of Physics, University of Duisburg, Germany.
Vladimir Belinski is at the International Center for Relativistic Astrophysics, Rome, Italy.
Please don't waste your time anymore on this blog and contact people who are a better match to your mission.
All the best,
Stefan
Hello Nick,
ReplyDeleteNick quotes William Unruh from the New York Times: "Maybe physics really is so weird as to not have black holes evaporate," he said. "But it would really, really have to be weird."
The thesis was also co-authored by Ralf Schutzhold and the summary includes the following counter argument to the validity of Hawking Radiation:
"However, we have also demonstrated counterexamples, which do not appear to be unphysical or artificial, displaying deviations from Hawking’s result. Therefore,
whether real black holes emit Hawking radiation or not remains an open question and gives non-trivial information about Planckian physics."
James
Hi Nick,
ReplyDeletethanks for dropping in and for your comments!
The presentation by Mangano at the CERN open day had been mentioned before - it indeed is well worth reading, and presents some of the points from the forthcoming paper by Giddings and Mangano currently under peer review, I guess.
Cheers, Stefan
PS: Dear Mr Tankersley, I feel no inclination anymore whatsoever to clear up your confusion - just ask these guys to help you stop the LHC, and don't waste your time anymore by commenting here on this topic.
Hi Bee and Stefan:
ReplyDeleteGlad you folks check back here frequently.
Bee, Oahu is nice, but somewhat touristy - I'm sure you noticed. The outer islands are much different, and much nicer. 80% of the population lives on Oahu [mostly in Honolulu]; and about 10%on the Big Island, and yet the Big Island is twice the land area of all of the other islands combined [and growing bigger - adding new real estate daily!].
I don't believe that invalidating "negative energy to infinity" models somewhow validates Hawking's model. And, it is not what I believe would be correct [as I mentioned], just what I believe would be more probable than Hawking's model. Further, I'm not certain it would require a 'to-infinity' component. As I mentioned, this was envisioned as being applicable for nearby [1 Angstrom away] particles, but let's not argue about something I don't hold a strong belief in favor of.
And no, I did not believe in a 'wall', or perhaps I misundertood your writing. Yes, nearby particles could infall, but for a microblackhole [tiny Schwarzschild radius], the gravity would be nearly zero at only 1 Angstrom distance, so 'infalling' is unlikely, yet 'tunneling' might not be.
Also, you and Stefan seem a little too vociferous in your attack on Jtankers.
He is not saying that the authors he cites necessarily invalidate Hawking. He is saying that they have concluded that Hawking's idea simply might not be proven true. That is quite a different conclusion. I have read the quotations he provides, and that is exactly what they state.
Now, from a psychological perspective, there is a lot of 'pressure' on folks to conform, even in physics. If you're going to lose your funding, or lose your position, or even believe you might be losing those things, for simply asserting [in a publication, etc.] that Hawking's idea might not be true, you're going to be very circumspect in how you state your conclusions [and I'm not speaking about the two of you - rather others]. Only exceptionally-well-tenured persons or persons no longer concerned with such academic concerns would feel free to speak more freely - persons such as Otto Roessler who is "pensioniert", or myself [now independent of government funding -whether direct or indirect].
Stefan, thanks for the email links. I will indeed contact those individuals. Who knows, maybe they've changed their minds; or maybe they are simply sitting back quietly waiting to be contacted.
As to Mangano's work, I've read his power point presentation given at Cal. I'm gratified to find he agreed exactly with me and other cosmic ray physicists I've been in communication with on this issue [who disagree with both of you about this], and concluded that the conventional "cosmic ray argument" is invalidated for the exact same reasons I concluded it is invalidated. He is indeed working on a "neutron star" version of the cosmic ray argument. My associates and I have concluded that it does not do the job, though we are looking forward to seeing the version put forth by Mangano.
And Bee, that is exactly the reason for the suit. We need the time to engage in a peer-review of anything Mangano's group puts forth. This is, after all, coming out at the 11.9th hour, when it should have been done at the first hour [of course, those other papers such as Helfer's hadn't come out yet then, either].
If you'd shown a little interest in reading the lawsuit, you'd know that that is why it was filed. Mangano's group promised Aymar they'd be finished by January 1, 2008. So Aymar wrote me last October, 2007 that that was what would happen. Then it didn't happen. Then I received written communication from them that they'd have it out by March 1, 2008. Then that didn't happen.
It's not my fault they shorted us on time; it's theirs.
And, why the rush, anyway? Is it to 'prove us wrong' by doing the collisions, and then saying "gee, we're still here - guess they were wrong" with a smug smile? The theories we've been examining show that even if these theories are correct, it should take decades or centuries to detect that anything went amiss.
Regards,
Walter
-----------
Hello, Walter. You posted this:
ReplyDelete"Until Hawking radiation has been observed [which might happen with our GLAST satellite and other planned gamma observatories], the simplest explanation is that it does not exist."
Can't I say the same for micro black holes? As far as I know, we have never observed a micro black hole, so by your logic, I can conclude that they don't exist.
-Nick
Hi James,
ReplyDeleteMy degree is in Computer Science and I only completed two semesters of Physics in college. But my IQ has been measured as at least 140 so problem solving and learning is not an issue.
Wow. How about you go learn quantum field theory in curved spacetime, and solve the problem of showing that black holes no not evaporate, since this seems to be what you believe. Then come back.
Why do you dismiss the concerns of these physicist?
I do not dismiss these concerns. I read the papers (the ones you mentioned and others), I thought about what they are saying, I concluded their arguments are implausible. I honestly don't know what else to tell you since you already said you are not qualified to judge on the content of these works, so any detail I could give you is useless you will only repeat your collected text passages one more time.
However, James Blogget who has a Masters Degree in Statistics conducted a Delphi study of 15 physicists and estimates [...]
You already mentioned this above. To repeat my reply 'this is a joke, right'? And since your IQ might be in the way: this reply of mine is meant to say I couldn't care less what somebody with an MD in statistics heard from 15 people who said they are physicists. What kind of an argument do you think this is?
Best,
B.
Hi Walter,
ReplyDeleteYes, I noticed Oahu is somewhat touristy. I'm not much of an island person anyhow.
I don't believe that invalidating "negative energy to infinity" models somehow validates Hawking's model.
I was trying to explain why your idea that the negative energy part of the particle pair which you think exists escapes to infinity and thus the black hole grows does not make sense. As I already said to JTankers above, Hawking evaporation has been derived by various different approaches that confirm the results in hundreds if not thousands of publications. The task is on your side: if you want to only raise a doubt about it you would have to find a consistent scenario in which black holes do not evaporate.
It is pretty obvious that you and your followers are clinging to the occasional idea doubting Hawking radiation. Such things happen in every branch of science - I would even say it is a sign that the research atmosphere is healthy. You should also have noticed that these ideas are in disagreement with each other, and if you would take them seriously would indeed invalidate each other. This is not exactly what I call self-consistent. It is a mystery to me how you can take that seriously.
but let's not argue about something I don't hold a strong belief in favor of.
I'm more than happy to drop the topic.
Also, you and Stefan seem a little too vociferous in your attack on Jtankers.
That might be because he did not listen to the first some iterations of this exchange and is wasting our time by demonstrating his ignorance.
He is saying that they have concluded that Hawking's idea simply might not be proven true.
You can't prove a theory true, you should know that.
Best,
B.
Dear Dr. Wagner,
ReplyDeleteI am just getting tired of this topic, and that may be explain my shrinking inclination for polite small-talk. There are no new arguments in this debate, just the new revelation of gross misconceptions, such as your assumption that the size of the putative mini black holes is on the order of Angstrom, where in fact they are about eight orders of magnitude smaller.
But of course, there is nothing wrong with not knowing these facts and being concerned about this issue and potential dangers of the LHC in the first place.
And I agree that handling by CERN of the safety issue could have been much better - not least because then it may be easier for critical, concerned people to convince themselves that there is no reason to worry. To me, the best place for a debate like this one seems to be the CERN site, where they do not offer the possibility, unfortunately - and I am less and less enthusiastic to use our blog as forum for the debate, as it is not our job and just wastes time.
OK, to sum up the official safety statements:
The RHIC safety reports by R.L. Jaffe, W. Busza, J. Sandweiss, F. Wilczek and Arnon Dar, A. De Rújula, U. Heinz, respectively, do not discuss the mini black holes which are possible in speculative theories with large extra dimensions, and which just started to be studied around the time the reports have been written.
The CERN Yellow Report by Blaizot et al. discusses the issue of mini black holes, and even the case of non-decaying holes, but this discussion (focussing on the diffusive motion of magnetic monopoles through the Earth) is a bit short. Moreover, the report focusses on heavy ion collisions, which will not be those with the highest energies at the LHC. To see why heavy ion physicists have a longer tradition of facing disaster scenarios, you may have a look at the nice historical survey by Joe Kapusta, Accelerator Disaster Scenarios, the Unabomber, and Scientific Risks.
A new, more comprehensive report focussing on the black hole issue by Giddings and Mangano apparently is under review right now, and the Talk by Mangano seems to sum up the main points of this report.
Here is my personal wish list of what should be discussed in a solid, quantitative way in such a report, in order to disperse any reasonable worries and make it clear that people who continue shouting "end of the world" after reading the report are irresponsible fear mongers or just plain crackpots:
Assuming the most "optimistic" scenario for the production of black holes compatible with well-known facts (that may be called the "one black hole per second" scenario, since such a number has been estimated for this case), what are the actual velocity distributions of this stuff, how much can be captured by the gravitational well of the Earth and the Solar System, respectively, and how does these numbers compare to the respective numbers for black holes constantly produced by cosmic rays in the atmosphere, elsewhere in the Solar System, and the mini black hole "background radiation" to be expected in such a scenario?
Assuming that the mini black holes want to play a dirty trick on us, do not like Stephen Hawking, violate CPT theorems, and do not radiate, what is the growth rate of those trapped in the Earth's or Solar System's gravitational well, using our knowledge about their cross section, the radius dependence of mass (since they "fill" the extra dimensions first, they could gain enormously mass without actually growing in radius)and the parton distribution of matter they will encounter? How does this compare with the observed universe, given the mini black hole background radiation to be expected in such a scenario?
Looking in detail at these points should allow to establish robust upper bounds for the probability that the Earth may be harmed by the LHC, and I am convinced that the outcome will show clearly that there is no danger.
However, it is true that a detailed investigation seems not to have been published yet (on the other hand, it has not much scientific value as such, which may explain this deficit), and that the current CERN pages "Safety at the LHC" and "Ask an Expert: LHC and black holes?" (this page is well worth reading, since it contains many facts and good arguments) are a bit wanting in this respect.
This is really a pity, since I can imagine that much of your concerns about the LHC, for example, could have been dispersed already years ago. On the other hand, you could not read your name in so many newspapers around the world.
But I do really not see why I should spend more time on this topic right now - and if you want to continue this debate, which is quite idle as long you as there are no new arguments, feel free to do it somewhere else.
Best regards, Stefan
Dear Dr. Wagner,
ReplyDeletelistening to Sabine and reading again your previous comments, I see that I may have misunderstood you about the size of the mini black holes - you seem to argue that the average distance of nearby matter is on the order Angstrom, which is correct. You do not refer to the size of the black hole.
Sorry about that.
However, its seems important to me to be aware of the "size" of the black holes, which is about 1/1000 the size of a nucleon, and that a nucleon for a black hole gravitationally trapped on Earth is more or less empty on this scale.
Best, Stefan
Stefan:
ReplyDeleteThanks for correcting yourself. Yes, I am aware that the microblackholes are much smaller than a nucleon.
As to your wish-list, we're working on it already. My associate in Germany [who works in neutrino physics and cosmic radiation physics] has a preliminary calculation of about 1E-8 as the small fraction that would be captured by Earth's gravity [and obviously much larger for that which would be captured by the solar system], though I have not reviewed his work as of yet. This is certainly not small enough to assure safety, though getting close with respect to Earth. Sure would hate to see the Sun turned into a black hole, though.
As to the natural background of microblackholes, they would all be relativistic relative to earth and not come into play. Because we can imagine that slow microblackholes interact differently than relativistic microblackholes, we also don't know anything about their accretion rate compared to the known low accretion rate for relativistic microblackholes [if they exist] due to the persistence of neutron stars, etc.
Perhaps part of the problem is the smugness of some theorists. When problems are pointed out with their theories [such as their theory that natural relativistic microblackholes would be the same as slow microblackholes that can be captured by Earth], they simply fall back and claim that Hawking Radiation is their back-up that will save us. Others point to bizarre scenarios such as "shaving" as being the cause of possible earth disaster, or that the LHC might also make "dragons". Frankly, I'm tired too of that kind of BS.
Regards,
Walter
Hi Walter,
ReplyDeletethey simply fall back and claim that Hawking Radiation is their back-up that will save us.
Because this argument is to our best present knowledge correct and you haven't brought up a single sensible reason against it. All you say is that you find things "odd" about Hawking radiation, or that there is a "problem that some physicists have" without explaining what the problem is or who "some physicists" are, you have some "believes" about what "would be more probable than Hawking's model", and then you try to explain "from a psychological perspective" why there is no consistent theory without Hawking radiation confirming these believes of yours. I already explained above why this "psychological perspective" you hold about the community is nonsense. Certainly, if there is such a lot of previous work on a topic as in this case, anything potentially in conflict with it needs to be done very carefully because a lot of aspects have to be taken into account. But if there was somebody who believed he could prove Hawking wrong, why on Earth should he hold back this conclusion? You don't usually get funded for the results you obtain, but for the topics you work on. And as you mention yourself, there is without doubt a large fraction of very self-confident people in the community who wouldn't have any problem whatsoever insisting they are right and everybody else wrong, provided they had a basis for it.
Perhaps part of the problem is the smugness of some theorists.
Though this might indeed be true, empty accusations like this aren't worth anything.
Others point to bizarre scenarios such as "shaving" as being the cause of possible earth disaster, or that the LHC might also make "dragons".
I have no idea what you want to shave, but I guess the mentioning of dragons refers to Arkani-Hamed's quote? Let me point out that had Arkani-Hamed et al not published their '99 paper, we wouldn't have this discussion altogether.
Frankly, I'm tired too of that kind of BS.
Really? Oh, I can relate to this. What is very tiresome for me is that I have no idea why I have to waste my time with this conversation. I haven't been working on the topic for several years, nobody at my institution works on the topic, and there are other things I find much more interesting. If you really wanted to contribute to the research on the field, why then didn't you apply for a grant 8 years ago, hired some people and put some publications out as this is usually done? I have already said above that CERN maybe should have paid more attention to the questions raised earlier, but I'm not the one to address complaints to.
Best,
B.
Dear Dr. Wagner,
ReplyDeleteAs to your wish-list, we're working on it already.
Oh, fine! I know Sabine has a slightly different opinion about that point, but I think one (you) could insist that someone (at CERN, or somewhere else) does such an actual calculation and presents the methods and assumptions used, and the results. And to repeat myself, while I do not doubt that the LHC is safe, I think it is unfortunate that this has not already been done a few years ago.
As to the natural background of microblackholes, they would all be relativistic relative to earth and not come into play.
Actually, I am not so sure about that. For the stuff constantly produced by cosmic rays, we are talking about the tiny tails in the rapidity distribution, which seem to be negligible - but the "experiment" has been running since billions of years, so one probably should plug in some numbers at least to be sure.
And there should be some primordial background from the big bang, which probably would be some "cold dark matter" and would not have to be relativistic. (One should also try to avoid that the model one uses implies that all matter has been sucked into mini black holes in the first microsecond of the universe or so...)
Also, relativistic mini black holes crossing a neutron star just once can for sure be used to establish bounds. I see no reasonable justification at all to doubt the validity of special relativity or the reliability of well-established hadron physics and parton distribution functions in this respect.
Another point is that slow mini black holes swallowing partons would get kicked around slightly, because of the relatively high Fermi momenta of the nucleons and momentum conservation, and even more so since they could momentarily accumulate colour charges and be subject to strong accelerations. Thus, slow mini black holes could effectively be kicked out (or diffuse out) of the Earth's gravitational well instead of "sinking" towards the centre of the Earth.
In principle, all that belongs to the "transport" part of the wishlist, and should at least be discussed qualitatively. One probably could make it even quantitative, somehow...
OK - but I'll leave it at that.
Best regards,
Stefan
Bravo Bee. I'm glad you are trying to debunk the fear mongering.
ReplyDeleteAlthough I am only a layperson, I am doing my best to quell fears on lhcconcerns.com by posting links to various blogs and sites by physicists who give good reasons why the LHC is safe (I also linked to this blog). Unfortunately, like you say, it is hard to argue with people who are closed minded, have no knowledge of the subject, and are only arguing for the sake of being right, not for the sake of rational discussion.
-Nick
Hi Nick,
ReplyDeleteThanks, I appreaciate your help.
-B.
I know Sabine has a slightly different opinion about that point
ReplyDeleteWell, maybe I should clarify my opinion, just so there are no confusions. I definitely think that one should pay attention to such raised concerns about scientific experiments in whatever field, and that such concerns need to be appropriately addressed in a timely manner. That does not mean however I think mini black holes at LHC will cause the end of the world - which was the topic of this post.
What annoys me about this story are three things.
For one, initiating a process to address concerns about potential risks is task of the collaboration, and calling theoretical physicists irresponsible because they work out and publish the details of theoretical models without attaching each with a risk estimate is completely inappropriate.
Second, the accusation that scientists would not dare to break consensus on the danger of causing the end of the world is a deliberate try to undermine the credibility of the scientific community without any reason whatsoever. I've explained previously that this paranoia is completely unjustified, and if you've ever worked in the field you know why. Theoretical physicists love to disagree with each other. Kapusta also mentions this in his paper "physicists relish challenging the
ideas, calculations, and measurements of their colleagues." The result of such accusations however is a damage to the reputation of the scientific community (in the larger sense) in a time when support, financially and ideologically, for scientific research is already too short given the challenges that we are facing.
Third, this discussion has been distributed in the media in very imbalanced way with no other purpose than to scare people who can't judge upon the actual danger anyway - and especially not when articles don't provide even the most basic information. And this is admittedly what pisses me off the most, there are sufficiently many other things people should seriously be worried about and should spend time thinking about it, newspapers print already enough bullshit, one doesn't have to support this tendency.
The fact that these points are so obvious, and neglecting them does so obviously hinder any constructive exchange, raises imo a lot of doubts about the intentions of the 'concerned' people. The only reason I can see to lead such a discussion by publicising catastrophe scenarios, and putting up websites to call upon people to write to their elected representatives is to draw attention to oneself and see the own name printed in a newspaper. A serious discussion could have been lead in the usual manner, by peer-reviewed publications (or even by not-peer reviewed), or a conference, or in some other sensible way.
Best,
B.
Being criticized for my contributions, I thought, hey, I am a victim too:)
ReplyDeleteWell now after letting the discussion runs it's course I wanted to "elevate the discussion" and relegate it to the valleys for consideration.
Since we've been taken to where Joe Kapusta has lead us in a scientific approximation, what value then to consider the theoretical framework when the chance for tunnelling exits? Does it?
The calculation of the energy used has to be applied to the particles that manifest, is this not correct?
What happens to the "remaining energy" that has not be given as particle evidence?
New life forms?:) Forgive me for my layman ignorance, Bee:)
Bee writes: "What is very tiresome for me is that I have no idea why I have to waste my time with this conversation. I haven't been working on the topic for several years, nobody at my institution works on the topic, and there are other things I find much more interesting."
ReplyDeleteI think Bee "wastes time" with this conversation because Bee started this thread by ridiculing those who, based on sound principles of ethics and risk management, question the safety of the CERN LHC. Answering such ridicule would seem to be a law of nature.
CERN management, by saying the probability of a mishap is zero and then failing to publish a safety analysis, effectively brought the lawsuit upon themselves, as I show here.
While I agree that theoreticians are not required to be experts in safety issues, it seems to me that one who embarks on a course of ridicule ought to have at least some acquaintance with the issues defined in the lawsuit. Risk (R), measured in Euros or dollars, is the product of the cost (C) of the undesired event and the probability (P) of that undesired event.
R = C * P
The undesired event in question is, of course, the complete destruction of the earth. For our purposes of establishing an acceptably low probability of planetary destruction, orders of magnitude are of sufficient precision.
Risk is not a fixed value. P in the risk equation is a variable. We can reduce probability by spending money to do research and analysis. Another way of looking at risk is to view it as the amount of money it would take to assure us that the probability is acceptable. That is, if it were to be shown that it would require as much money to prove safety as the LHC were to cost, that could influence a decision embark on the project (too late for that now). Therefore, an upper bound on an order of magnitude estimation of an acceptable risk is about the cost of the LHC project itself (10 billion dollars).
One way to roughly establish the value of the earth is to take the annual gross economic product of the earth and multiply it by the life expectancy of the earth. The annual economic product of the planet is on the order of 10 trillion (10^13) dollars and the expected economic lifetime of the planet can be assumed to be 100 million (10^8) years, for a cost of planetary destruction on the order of 10^21 (a thousand billion billion) dollars.
I chose 100 million years because that is one estimate of the time it will take for the sun to become a red giant, making life on earth impossible anyway. If you prefer a longer or shorter time, that can be negotiated, but without a catastrophic event, we have to assume the earth will last a fairly long time. We must include future value, because future people are also stakeholders in the project. To do otherwise (as some have suggested) is unethical, a proof of which is beyond the scope of this particular post, but I suggest that those who take issue with this proposition do some research on ethics. As an aside, it could be argued that by the time the sun becomes a red giant, people will have moved out into space, but putting infinity into equations isn't practical and is not necessary to my thesis.
Now recall that our upper bound on R is 10^10. Then we have from the risk equation:
P = 10^10 / 10^21 = 10^-11
Therefore, a safety evaluation that shows acceptable risk will assign a probability of planetary destruction to be less than 10^-11 (one percent of a nano-worry). The probability estimates I have seen quoted from some CERN theoreticians are "one in a million." That's not good enough (by five orders of magnitude). QED.
That one percent of a nano-worry is not for each LHC collision, but for all the collisions over the lifetime of the LHC. My main point, and the point of the lawsuit, is that a credible safety review to ensure safe operation of the LHC ought to be openly performed before collision operations commence. Thank you for the opportunity to respond.
Rick
Hi Rick,
ReplyDeletePlease read my previous comment, and maybe also re-read my post. I have never ridiculed "those who, based on sound principles of ethics and risk management, question the safety of the CERN LHC" as you put it. This again is a completely unjustified accusation. I've always tried to take these concerns seriously, and I've during the last years answered a lot of concerned emails/questions/comments from many people as good as my time allows it. Best,
B.
The annual economic product of the planet is on the order of 10 trillion (10^13) dollars and the expected economic lifetime of the planet can be assumed to be 100 million (10^8) years, for a cost of planetary destruction on the order of 10^21 (a thousand billion billion) dollars.
ReplyDeleteYou maybe should take into account that the dollar currently is losing value, and integrating inflation over 100 million years, you could add a few extra zeros to your number or so... Moreover, you should not forget to include an annual growth rate of, say, modest 0.1 percent, yielding another factor 10^43500 ;-).
This is the most fascinating silly estimate I have seen in a very long time.
I think it is time to close this thread?
Stefan:
ReplyDeleteI believe the point that Rick was trying to make is that there has to be a starting point to engage in any risk analysis.
What if the LSAG comes back [they won't] and says that they can calculate that there is only a 1 in 1,337,000 chance of planetary destruction. The question then becomes, is that an acceptable probability. How do we calculate whether that is an acceptable risk.
This Risk Estimate is actually fairly standard in many fields of engineering, though of course not for destruction of the entire planet.
While you may find it silly, others do not.
The other point being made, of course, is that we have to have exceptionally strong confidence in our probability estimates. Stating that they are the same as "creating dragons" is not an acceptable methodology.
Regards,
Walter L. Wagner
Hi Walter, (if this is truly he)
ReplyDeleteThe only thing I can add to the conversation is to pray that the judge you face recognizes who you and your group of seven are, in terms of credentials and expertise and therein give it the proper weighting against those you slander and libel with your pseudo science, exaggeration and tactics of terror as to end this foolishness swiftly before it gains anymore unwarranted momentum. However, I am somewhat fearful that he may be a frequent listener of Coast to Coast and believe your concerns warrants the same serious consideration as Big Foot, another intelligent species residing beneath the earth or alien abductions and have this all be raised to another level.
Best,
Phil
Hi Walter,
ReplyDeletethere has to be a starting point to engage in any risk analysis.
A starting point to engage in any analysis is understanding the basics.
While you may find it silly, others do not.
Nobody said asking for a risk assessment is silly. So would you please stop with your continued affected indignation about the allegedly irresponsible theoretical physicists?
To repeat it one more time, the reason why I very much dislike these developments is the unwillingness of the catastrophe proclaimers to actually learn anything. Instead, there is the strong tendency to construct arguments without any scientific basis. Just read through this thread. I have wasted a lot of words trying to explain why the raised concerns there might be no Hawking radiation are unjustified, with the only outcome you are changing the topic.
The other point being made, of course, is that we have to have exceptionally strong confidence in our probability estimates. Stating that they are the same as "creating dragons" is not an acceptable methodology.
If you have a problem with Arkani-Hamed's sense of humor, I'm not the one to complain to. I found it funny. I would be really interested to learn about your estimate how likely it is that black holes do not emit Hawking radiation.
Best,
B.
Warning: Off topic....
ReplyDelete....so much for the Brain fart above:) Logic:False teeth, are white too.:):):)
Much of understanding the Big Bang is extrapolating between knowledge of particle physics today, and projections from the mathematical model of an expanding universe in general relativity. The Einstein equations give us a mathematical model for describing how fast the Universe would expanding at what size and time, given the energy density of matter and radiation at that time. We base our guesses about the matter and radiation density of the early Universe based on the ancient light reaching us from the past in our night skies, and what we have learned about elementary particle physics, through theory and experiment.
Corruption on the internet rampant?:) Clifford talks about a movie to consider, Bee?
And afterlives, "are" really interesting:)I can't point to a location in the brain either, other then to say, it may be reptilian?:)
But removing the "weight of repeated patterns" can really be uplifting. Goes to the core, of what the problem may be, "if" there is one existing.
A book perhaps in relation to Homer Dixon and Marshall McLuhan? One persons quest to find "the key modelled properly," and the methods of it's use, for everyone, mastered. Methodology.
And then maybe lead into, the ingenuity and space created for the next generation, where there is nothing left to do.
Don't think so.:) And life goes on, it in cyclical process, Dante's vision, sees it as a "long cry from the light."
Best,
"One way to roughly establish the value of the earth is to take the annual gross economic product of the earth and multiply it by the life expectancy of the earth. The annual economic product of the planet is on the order of 10 trillion (10^13) dollars and the expected economic lifetime of the planet can be assumed to be 100 million (10^8) years, for a cost of planetary destruction on the order of 10^21 (a thousand billion billion) dollars."
ReplyDeleteYou have a good sense of humor, Rick. Er, it is a joke, right?
Stefan and Bee:
ReplyDeleteDr. Helfer has responded to an email and has this to say about this entire blog [which I quote without permission, though I believe he would not mind}:
"I have glanced at the blog; you can understand that for me to comment on it in detail would require a great deal of time. The statement you quote, to the effect that there is no doubt about the existence of Hawking radiation, is wrong. Beyond that, I will only say here that it does not look like a very good discussion -- there are significant inaccuracies, and the analysis seems not to go very far."
In concur with his analysis.
Regards,
Walter L. Wagner
Hi Walter,
ReplyDeleteCorrect, the analysis in this blogpost does not go very far. And yes, it certainly does not look like a good discussion. Your content free quote doesn't improve anything about the quality of this exchange, it adds exactly no information to the topic at hand. Best,
B.
Hello Bee:
ReplyDeleteActually, the quote I provided was in direct response to your assertion that you "have wasted a lot of words trying to explain why the raised *concerns there might be no Hawking radiation are unjustified*... "
In fact Dr. Helfer asserted that your assertion is wrong, and that there is in fact doubt about the existence of Hawking radiation.
That was the thrust of that quote.
That also goes to the tenor of "closed-mindedness", I believe, that when presented with such evidence, it is simply disregarded and treated as if it does not exist.
I get that a lot from people at the LHC.
Regards,
Walter L. Wagner
Dear Dr. Wagner,
ReplyDeleteI didn't say that insisting on a proper risk analysis is silly.
On the contrary, I am well aware of the analysis by Adrian Kent, for example, that the RHIC safety reports had been wanting in this respect, and that even if highly risk-tolerant assumptions are made and no value is placed on the lives of future generations, a catastrophe risk no higher than ≈ 10^(−15) per year would be required for consistency with established policy for radiation hazard risk minimization.
Moreover, my personal impression is hat CERN could have reacted better to Kent's suggestion that future policy on catastrophe risks would be more rational, and more deserving of public trust, if acceptable risk bounds were generally agreed upon ahead of time and if serious research on whether those bounds could indeed be guaranteed was carried out well in advance of any hypothetically risky experiment, with the relevant debates involving experts with no stake in the experiments under consideration. (Both quotes from "A critical look at risk assessments for global catastrophes" by Adrian Kent, arXiv:hep-ph/0009204, published in Risk Analysis 24 (2004) 157-168.)
I just had the impression that this "economist's estimate" may not be very helpful a contribution to a serious discussion.
By the way, did Adam Helfer tell you that mini black holes do not radiate at all, or is this issue about the specifics of Hawking's calculation?
Best regards, Stefan
Hi Walter,
ReplyDeleteActually, the quote I provided was in direct response to your assertion that you "have wasted a lot of words trying to explain why the raised *concerns there might be no Hawking radiation are unjustified*... "
In fact Dr. Helfer asserted that your assertion is wrong, and that there is in fact doubt about the existence of Hawking radiation.
I never said there "there is no doubt about the existence of Hawking radiation" and I agree with Helfer it is wrong to say there is no doubt: Obviously, there is doubt, your very existence is proof for this doubt. I said instead I don't know any physicist who doubts that black holes radiate. I don't know Helfer. I never met him, I never heard him giving a talk.
It seems you totally did not get my previous comment. It was meant to say the quote you provide does not contain any argument. Please explain me, what fact raises the alledged doubt? Please tell me why Hawking radiation does not exist. I am not interested in what Helfer wrote you in an email if it doesn't contain any information. This is why all these words are wasted: you have not offered any scientific argument as to why Hawking radiation does not exist. If I ask you to, you produce fog of one kind or the other, after you wisely dropped your own idea how non-radiating black holes could come across.
That also goes to the tenor of "closed-mindedness", I believe, that when presented with such evidence, it is simply disregarded and treated as if it does not exist.
If you read my post and the comments here you will notice that I did not disregard Helfer's work and never treated it as if it does not exist. Again, your accusations are unjustified.
Best,
B.
Stefan:
ReplyDeleteAdam Helfer's comments to me were quite brief, and did not go farther than to say it is wrong to assert that Hawking Radiation is not disputed, and that he stood by what he's written previously.
He also indicated that he is willing to engage in communication with any physicist who contacts him. I gather he does not [like most scientists?] engage himself in blogging about science.
You, Bee, I, and a few others appear to be the exception about science blogging. I blog quite frequently at www.sciforums.com, where I also learn a tremendous amount, since there are always excellent posts about recent news in astrophysics, particularly those postings by Blobrana. Unfortunately, most of the people who post there are not scientists [which I find true at most science blog pages], but there are several who are, and we know each other by blogging reputation.
To reiterate what's been written in the science literature about Hawking Radiation and how it is disputed, I quote Ralf Schuetzhold:
"However, we have also demonstrated counterexamples, which do not appear to be unphysical or artificial, displaying deviations from Hawking’s result. Therefore,
whether real black holes emit Hawking radiation or not remains an open question and gives non-trivial information about Planckian physics."
http://arxiv.org/PS_cache/gr-qc/pdf/0408/0408009v2.pdf
That is essentially what Helfer himself had written in 2003: "... Yet this prediction [that blackholes radiate] rests on two dubious assumptions ... [there is] no compelling theoretical case for or against radiation by black holes":
http://www.arxiv.org/abs/gr-qc/0304042
I don't believe anyone is claiming that they have found errors that prove that blackholes can't radiate -- though that does seem dubious to me, which I won't discuss anew.
What is being claimed is that there is a significant doubt that Hawking Radiation is real in some quarters of science, and since it is not possible to prove it true without experimentation, it is not proper to rely upon it for safety considerations.
I believe, actually, that CERN's LSAG came to that same conclusion.
What I have found alarming is that what has been evaporating has been the safety argument previously presented by CERN, and even more so when the LSAG has agreed with me on those issues [unreliability of using Hawking Radiation for safety; conventional cosmic ray argument not valid due to MBHs relativistic in nature, grav. trapped if made by LHC]. I find rather that such concurrence with my thinking is quite refreshing, as you can imagine.
Regards,
Walter
----
Here's one more, just for good measure:
ReplyDeleteProf. V. A. Belinski: Physics Letters A 209 (1995) 13-20, National Institute for Nuclear Physics (INFN) and International Center for Relatiuisric Astrophysics (ICRA), Rome University “La Sapienza”, Rome 00185, Iraly; Received 1 September 1995; accepted for publication:
On the existence of quantum evaporation of a black hole.
"A conjecture is made that the standard derivation of the black hole evaporation effect which uses infinite frequency wave modes is inadequate to describe black hole physics. The proposed resolution is that the problem is not due to the absence of the as yet unknown 'correct' derivation but rather that the effect does not exist. ... [it is thus shown that]no permanent evaporation process can exist."
Hi Walter (At least we think you are),
ReplyDeleteI find it curious that you have found this post so much to your interest. I wonder if it could be connected with the preparation of your upcoming court appearance in relation to your action. Perhaps you plan to use some of what is found here in the presentation of your case. Are you planning to take some of this out of context as to have it appear to indicate that Bee and Stefan comments lend credence to your position? Therefore, in an attempt to address this concern, how about a straight answer for a change where you simply address the question with a yes or no?
I think it to be unwise and somewhat dangerous to perhaps only concentrate on your level of expertise in regards to the subject and forget the fact that you also studied law. My intent is simply to raise the point that one should not assume your competency in one respect can be automatically assigned to be consistent in another.
Regards,
Phil
Hi Walter,
ReplyDeleteIt seems to me we really have a fundamental misunderstanding here about what constitutes a scientific argument. All you do is citing sentences from other people's papers, papers whose content you evidently do not understand. What I am asking for is an explanation as to how Hawking's calculation fails.
The three references you provide have all been mentioned before. Belinski has published essentially the same calculation several times over more than a decade (I looked up the paper Flavio mentioned above and figured it looks very familiar). As far as I can say, his approach is mathematically sound, but unphysical as his wavefunction covers causally disconnected regions of spacetime. He argues that the initial stages of collapse are in Minkowski spacetime (p. 14) notwithstanding the fact that the causal structure is a global feature. It is not a Minkowski space-time in the initial state, but the space-time is asymptotically flat (thus the metric is that of Minkowski space). I do not find his argument plausible.
It is good that you inform us Helfer stands by what he's written previously, because I've told you now three times he does not say Hawking radiation does not exist. I have further explained, that I do not find his work particularly convincing because he does not compute anything, so one can't even say whether it was already in disagreement with observation if it was correct (and it seems to me the effect he is claiming exists should be substantial even in the asymptotically flat region).
It is interesting you point out the paper by Unruh and Schützhold, which I like very much. It demonstrates very nicely how the Hawking effect 'does not depend on the details of the dispersion relation at high wavenumbers', and they examine under which conditions this conclusion holds. In the second half of the paper they study circumstances in which one would have deviations from Hawkings thermal spectrum, but I can not see how their calculation implies that black holes do not radiate. Nick above was already so nice to provide a quotation from Unruh putting his work into context: "Maybe physics really is so weird as to not have black holes evaporate. But it would really, really have to be weird.”
This paper should also be interesting for you with regard to Helfer's calculation (I assume he knows it), since he does base his criticism exactly on the trans-planckian modes that Unruh and Schützhold show the effect is independent of under quite general circumstances and Helfer thus had to explain in exactly which way and why these assumptions do not apply in his approach (if he explained it, I must have overlooked it). Btw, Helfer also claims that these 'Planckian energies' mean 'the onset of an essentially quantum gravitational regime, in the vicinity of a black hole' (see here), which is just not the case, as I explained in my blogpost above.
So I repeat my question again, could you please tell me on which model your doubt is based that black holes do not emit radiation and in which way Hawking's conclusion is invalidated?
Best,
B.
Hi Bee:
ReplyDeleteWell, at least we can agree to disagree [as they say].
I do agree the Helfer and the others cited do not show Hawking wrong. Rather, they show that Hawking does not have to be right. That's all.
They call into question whether Hawking Radiation can actually exist, without trying to prove that it cannot.
And you know what, physics is really really, weird, and getting weirder all the time [or at least, some people say]!
And Phil should know that anything we type here would be considered inadmissible hearsay in most legal contexts. What this and other blogs does do is give me information [references to science articles, etc.] and ideas which I will certainly be able to use. And that is the whole purpose of these and other blogs, as I imagine it.
Let me know when you next plan to visit in Hawaii, and in particular here on the island of Hawaii for which the Kingdom, Republic, Territory and State were named after, and I'll give you that tour if you wish.
Regards,
Walter
Another practical argument against the black hole doomsday scenario.
ReplyDeleteIf our understanding of physics is so far wrong that all of this blog's explanations are false, then it is hard to believe that the LHC would function at all. In fact, if someone believes that our understanding of quantum mechanics is seriously flawed, they should be expressing concern about the far, FAR more likely implication that the LHC will simply blow up or malfunction. This would also be a tragedy (though not an Earth-threatening one).
(Please note that I do NOT think that is likely at all)
Also, I do not think it has been mentioned here, but one of the most compelling cases for Hawking Radiation (to a layman such as myself) is that it makes black holes consistent with the laws of thermodynamics.
Many thanks for all the info shared here,
MP
Hi Walter,
ReplyDeleteYes, I agree to disagree. I hope I could at least clarify why I am not concerned. It is not for the sake of not wanting to break consensus or preferring the safety of the majority opinion, but simply because the few arguments against Hawking radiation are very implausible to me, and I guess that most of my colleagues share my opinion (though I wish more of them would voice their opinion more clearly).
And you know what, physics is really really, weird, and getting weirder all the time
Theoretical physics is getting more abstract, but I wouldn't call it weird. There are aspects about the research environment that are getting weirder all the time, but that's a different story altogether.
I will likely seek for an escape from the Canadian winter next year, so if my way leads me to Hawaii again I might come back to your offer.
Besides this, thanks for staying polite, I appreciate this.
Best,
B.
Bee Writes: “Besides this, thanks for staying polite, I appreciate this.”
ReplyDeletePlease afford me the same courtesy. My comments are honest and sincere, though perhaps opinionated.
Steph writes (of his wife Bee I assume) “you can feel free of course just to dismiss the comment about Helfer's argument by a researcher who has been working on this stuff since nearly ten years (I am talking about Dr. Sabine Hossenfelder, currently at the Perimeter Institute”
My issue is not with the credibility of Dr. Sabine Hossenfelder’s, my issue is with the credibility of Dr. Stephen Hawking. I found his book “A Brief History of Time” to be so contradictory of Dr. Albert Einstein’s relativity theory, and his concepts such as travel back in time to be so offending to my common senses, that I lost faith that Dr. Stephen Hawking’s theories as anything more than creative speculation and conjecture.
I researched further and could find no credible reason that Dr. Stephen Hawking, an academically unexceptional student in the words of one of his professors, would be given the same position at Cambridge that was held by one of history’s greatest scientists, Sir Isaac Newton. I had to speculate that this most probably was a gift to a man dying of ALS.
My issues with Dr. Hawking's credibility were the reason that I first became suspicious that there might be a danger from creation of micro black holes. Because I learned that we would be safe if micro black holes were created, because of an unproven theory by Dr. Stephen Hawking that, in his own words “Einstein was doubly wrong”, black holes will evaporate.
I recently read that Dr. Hawking has conceded that at least one fundamental aspect of Hawking Radiation was wrong (information loss). Now Dr. Hawking proposes the concept of multiverses, which is debated as to whether this concept is more pseudoscientific than scientific in the recent issue of NewScientist this week (Issue No2655, May 10-16 2008), article: Some Swans are Grey by Robert Matthews, “…debate about whether concepts like the multiverse are really scientific?”
I have the greatest respect for physics masters such as Sir Isaac Newton and Dr. Albert Einstein. But while I have no reason to doubt that Dr. Stephen Hawking is a good, well meaning and clearly creative person, I honestly do not have confidence in his scientific opinion as being more than creative speculation, and I am not alone in this opinion, as at least one of his peers has called some of his theories poorly reasoned ideas that Dr. Hawking holds to for decades until proven wrong.
Thank you for entertaining my honest and sincere concerns.
JT
Correction: "I lost faith that Dr. Stephen Hawking’s theories [were] anything more than creative speculation and conjecture."
ReplyDeleteJTankers, I think this has been explained to you over at xcld, and it has been mentioned at this blog. If you only consider general relativity, why are you worried that black holes are going to be formed in the first place?
ReplyDeleteNick writes “...why are you worried that black holes are going to be formed in the first place”
ReplyDeleteHello Nick, I don’t know if your argument has merit, but CERN has predicted on their safety web site that micro black hole formation will not be an unexpected event, possibly at a rate of one per second. I see no reason to doubt this prediction.
Can you explain why Nobel Laureate Dr. Eric A. Cornell of the University of Colorado is not able to fully explain why a stable micro black hole is not a reasonable explanation for thousands of atoms that went missing after an unexpected “bosenova” implosion of a "super atom" containing approximately 16,000 rubidium 87 atoms at 3 nk (3 billionths of a degree above absolute zero), occupying virtually the same space that a single non-Bose-Einstein condensate atom would normally occupy, that imploded after the atoms were induced to attract each other rather than repel?
nobelprize.org/nobel_prizes/
physics/laureates/2001
/cornellwieman-lecture.pdf
I think this suggests there may be multiple methods of creating micro black holes, and we do not know with any level of confidense what the safety implications are of creating such exotic matter on Earth.
JTankers,
ReplyDeleteAnd now we have come full circle. Excellent. You have used those arguments before. They have been debunked and explained to you by physicists. Please quit reposting the same stuff over and over again.
Hi JTankers,
ReplyDeleteMy issue is not with the credibility of Dr. Sabine Hossenfelder’s, my issue is with the credibility of Dr. Stephen Hawking. I found his book “A Brief History of Time” to be so contradictory of Dr. Albert Einstein’s relativity theory, and his concepts such as travel back in time to be so offending to my common senses, that I lost faith that Dr. Stephen Hawking’s theories as anything more than creative speculation and conjecture.
Are you saying you want CERN to stop the LHC project because you read a pop sci book and didn't like it?
I didn't like "A brief History of Time" either, and I also didn't understand it. In fact, my disliking of Hawking's book was one of the reasons why I studied physics. It took me many years to understand the details of black hole radiation. If you want to overcome your problems, I recommend you read the following books
Quantum Fields in Curved Space (Cambridge Monographs on Mathematical Physics)
By N. D. Birrell, P. C. W. Davies
Quantum Field Theory in Curved Spacetime and Black Hole Thermodynamics (Chicago Lectures in Physics)
By Robert M. Wald
Black Hole Physics: Basic Concepts and New Developments (Fundamental Theories of Physics)
By V. Frolov and I. Novikov
If you think something is contradictory with Hawking radiation, it would greatly help if you could formulate precisely what you think it is.
I have no clue in how far it is relevant to the question of mini-black holes at the LHC what Hawking believes about time-travel.
Despite the use of words like 'supernova', 'collapse' and 'instability' in the Nobel Prize lecture, the properties of BEC in magnetic fields have nothing to do with black holes. Neither does the paper about 'fireballs' and 'dual black holes' have anything to do with the topic we're discussing here. I'm a physicist, not a linguist, and I'd appreciate if you'd discontinue such utter nonsense.
But while I have no reason to doubt that Dr. Stephen Hawking is a good, well meaning and clearly creative person, I honestly do not have confidence in his scientific opinion as being more than creative speculation
As a scientist, you aren't supposed to believe in anything because you have confidence in a person or his opinion. You're supposed to understand the argument and make up your own opinion. Your reasoning is a perfect example of an argumentum ad hominem, you are trying to raise doubt about the person making a statement, not about the statement itself. It is just not a valid argument. Please read this, and this, and maybe you will realize that not a single one of your 'arguments' is valid.
Best,
B.
Hi Bee,
ReplyDelete“If you want to overcome your problems, I recommend you read the following books”
Well I guess we won’t be hearing from him for a few weeks :-) Seriously though aren’t you making an assumption that he has a fundamental understanding of statistical mechanics as in relation to thermal dynamics? Although it is a bit outdated you could then also recommend - Thermal Physics - Charles Kittel/Herbert Kroemer - W.H. Freeman and Company (1980).
This should keep him busy at least another few days :-)
Best,
Phil
Hi Bee,
ReplyDeleteOne other observation in relation to what you just said to JTanker, as is refers to this action of Walter’s. That is, in as we can’t expect the judge who is to decide on the matter to have any great understanding of the matters, as they relate to the science or risk assessment; therefore in essence he will be forced to decide matters as it relates to the credibility and expertise of those presenting the arguments.
This has me somewhat (although mildly) concerned that there is a chance that Walter’s spin might hold sway over other opinions in such a context. One must remember that it is not only the weak minded that are taken in by the spin doctors of the world. This for me forms to be the real concern as to the nature of the danger presented. I have no concern that the dragons might consume us, yet I am somewhat worried that Walter might have the judge to believe in dragons.
Best,
Phil
I find the arguments against black holes eating Earth rather convincing. However, if I may fearmonger a bit more:
ReplyDeleteCan we fully rule out the possibility that LHC will create a "baby universe"? If not, then it seems to me that this raises its own ethical issues that don't have anything to do with our safety.
This New Scientist article discussing a paper by Sakai et al. suggests that we can't rule out completely that it might happen through monopoles (even though it's very unlikely). Is that right? Ideally there'd be a proof that either 1. baby universe creation at LHC is not possible, or 2. it already happens all the time anyway. It seems likely that cosmic rays would suffice to prove "2", but I'm not 100% sure; anyone?
According to Mangano's talk the cosmic ray argument rules out the monopoles eating everything scenario, but could there still be monopoles that don't eat everything but that do spawn a baby universe?
(Note, I don't have enough understanding of physics to make any claims, and probably there's a simple argument that shoots this all down.)
I'll be sure to inform the judge that Phil thinks she's a he, and that Phil thinks she's weak-minded, having never met her and knowing nothing about what judges do.
ReplyDeleteWalter L. Wagner
Hi Walter,
ReplyDelete“I'll be sure to inform the judge that Phil thinks she's a he, and that Phil thinks she's weak-minded, having never met her and knowing nothing about what judges do.”
I’m truly sorry as I did unintended have it sound like Judge Helen Gillmor was a man. As to calling her weak minded, if one reads what I said that’s totally incorrect as well as misleading, as I said “One must remember that it is not only the weak minded that are taken in by the spin doctors of the world”, which was to stress that she was not to be regarded as such. This is one example of what I refer to as spin and you can be certain that I don’t believe she would fall for such at the level you present here. As for what judges do, I suspect that is given away in what they are referred as.
Best,
Phil
Bee writes: "my disliking of Hawking's book was one of the reasons why I studied physics. ...I recommend you read the following books"
ReplyDeleteWhich aspect of micro black hole shrinkage theory should I concentrate on, and which books (or articles, web sites, etc.) might best explain the most likely method that would explain how energy entering into a micro black hole in the form of matter, anti-matter or both, might be expected to cause the micro black hole to lose energy rather than gain energy?
I find this concept extraordinarily non-plausible. So please help enlighten me as to how adding energy to a system could cause the system to lose energy, and why this should be an expected outcome. Why should I not conclude that the reason this is believed is other than that this was proposed by Dr. Stephen Hawking who was given a high academic position for reasons unclear to me, and for more than 30 years physicists have attempted to explain why Dr. Hawking might have been correct, while other physicists have attempted to explain that this theory is not supportable and do not have any degree of confidence in the same.
Again, where in science is it shown that adding energy to a system might cause the system to lose energy? Where has this been empirically observed in any context?
Thank you,
JT
Also, I was not comparing BEC (Bose-Einstein Condensate) matter to mbh (micro black holes), I was only reporting that Dr. Eric Cornell reports that in one incident, after stable BEC was created, after thousands of atoms were already compressed into approximately the space of a single atom, that a subsequent unexpected and not yet fully explained implosion appears to have compressed the thousands of atoms further into a space far less than the size of a single atom, and Dr. Eric Cornell does not rule out the possibility that this may have resulted in stable mbh formation, and that stable mbh may explain the mysterious disappearance of approximately half of the atoms involved in the experiment. Are you saying that this incident may not be relevant to the micro black hole discussion?
Hi JTankers,
ReplyDeleteand which books (or articles, web sites, etc.) might best explain the most likely method that would explain how energy entering into a micro black hole in the form of matter, anti-matter or both, might be expected to cause the micro black hole to lose energy rather than gain energy?
I referred you above to three very good books that will introduce you into the basics. I also explained repeatedly that the black hole does not lose energy because matter falls into it. I have also explained previously (here and here) that I dislike the explanation with Hawking-evaporation from particle pairs at the horizon for exactly this reason - and I guess this unfortunate pop-sci explanation is what your misunderstanding is based on.
I have also mentioned above that it might be more helpful to think of it as a tunnel effect, and I have also mention that this paper might be helpful.
after stable BEC was created[...] Are you saying that this incident may not be relevant to the micro black hole discussion?
Indeed, this is what I am saying.
Best,
B.
JTankers,
ReplyDeletePerhaps you are unaware that it is not Albert Einstein who deduced that black holes should exist. In fact, he initially doubted their existence, even though it was a consequence of his own theory of General Relativity. Even Schwarzchild, who did first predict them based on GR, doubted they would actually exist. In fact, it was Hawking who helped demonstrated that black holes are an inevitable conclusion based on GR.
This is how science works. A theory is not believed to be correct because its original author is infallible. Bee has already stated this, but perhaps some of this historical context will help make things clearer.
Einstein was not right about everything, and neither is Hawking. We only believe in their theories because they have held up to decades of testing and scrutiny.
Actually, when Hawking came up with his idea [circa 1974] of "evaporating black holes", the idea of collapsed-star black holes was well established and accepted in the physics community. It was one of the topics of discussion I had quite frequently at Cal with the grad students and post-docs I was working with. The idea that there might be 'bits and pieces' of singularity left over from the big bang, called primordial black holes, that was intriguing, and is apparently what gave Hawking his idea to propose an explanation as to why they are no longer around [if they are not!]. He concluded that there might be some bits and pieces that were large enough [mountain size] when formed some 14 billion years ago that they might just now be in the final stages of evaporation, and detectable in the Halo of our galaxy, where he said we'd find them "flaring like a christmas tree".
ReplyDeleteI believe Bee is correct in her comment about the Bose-Einstein condensate.
The volume of an atom is HUGE compared to the volume of a nucleon. Simply having lots of atoms overlapping each other in the volume of an atom [roughly one cubic Angstrom] would do little towards achieving the energy density that will be reached by the LHC, in which the kinetic energy [equivalent to thousands of amu masses] will be compressed into the 'volume' of a single nucleon.
Walter L. Wagner
M*P*Lockwood:” Perhaps you are unaware that it is not Albert Einstein who deduced that black holes should exist. In fact, he initially doubted their existence, even though it was a consequence of his own theory of General Relativity. Even Schwarzchild, who did first predict them based on GR, doubted they would actually exist. In fact, it was Hawking who helped demonstrated that black holes are an inevitable conclusion based on GR.”
ReplyDeleteBlack holes are not inevitable conclusion based on GR. There is no any empirical evidence of their existence. It was demonstrated many years ago that this solution may be “gauge” removed by the proper choice of the coordinate system (ref frame). Black holes are popsci hoopla which has nothing to do with physics and nature (by definition).
Regards, Dany.
Hi Walter/JTanker
ReplyDeleteYes, this is the reason why the black-holes in the BEC assertion is nonsense. Maybe I should have explained it, but I thought it is obvious: the density is far too low, we'd have produced them all the time at already existing particle colliders during the last decades. Why all the talk about black holes at the LHC? Because there we will squeeze more mass into a small volume than ever before. Best,
B.
Walter: when Hawking came up with his idea [circa 1974] of "evaporating black holes", the idea of collapsed-star black holes was well established and accepted in the physics community
ReplyDeleteThat comes as a surprise to me. I can recall plenty of discussion even in the early to mid nineties on whether astrophysical black holes actually exist. The situation only clarified with increasingly more convincing data about super-massive and later solar-mass black holes. But possibly things were different elsewhere.
M*P*Lockwood: In fact, it was Hawking who helped demonstrated that black holes are an inevitable conclusion based on GR.
Dany: Black holes are not inevitable conclusion based on GR.
I think M*P* referred to the singularity theorems (Hawking & Ellis, The Large Scale Structure of Spacetime).
One has to be careful with what one is talking about. To begin with one has to clarify what one means with 'black hole'. I would say it is the existence of a trapped surface. This does not necessarily mean there is a singularity inside. Though this has to be the case in GR, one would expect there to be QG effects that come into play, such that the singularity is actually avoided.
But no, black holes are not an inevitable conclusion based on GR. This couldn't be the case since you need to say something about the equation of state of the collapsing matter.
There is no any empirical evidence of their existence.
Depends on what you mean with that again. It is hard to show the existence of a horizon. It is impossible to find out whether there is a singularity behind a horizon. But we have plenty of evidence for objects that are so dark, heavy, and small that every explanation other than a black hole seems very constructed. Black holes are just the most plausible explanation for these observations and they fit very well into our theories. Best,
B.
Bee:
ReplyDeleteThe high-energy/astrophysics physics community was much smaller back then, but yes, the idea of collapsed-star blackholes had been around for decades already in 1974 when I was discussing its ramficiations with others. Lots of books, even, had been written about them. None had been detected indirectly, but searches were being proposed.
The idea that the Universe was on the inside of a "reverse black hole", i.e. one that was expanding instead of contracting, was also out there being discussed. I believe that is where Hawking came up with his idea, that bits and pieces of the singularity did not expand with the bulk of the universe expansion, remaining behind, trapped inside, as "primordial black holes". I'll look for one of my old books from back then about black holes and get you the cite. This really is 'old news'.
And yes, I thought the BEC was self-evident that it could not have been from a blackhole, though I'm not certain if they have a full explanation as to that experiment. Makes you wonder about the experimenters when they conjecture along such lines. Kinda like LHC theorists who go off about "cosmic ray arguments".
Walter
Hi Bee,
ReplyDeleteBee:” I think M*P* referred to the singularity theorems…This does not necessarily mean there is a singularity inside. Though this has to be the case in GR, one would expect there to be QG effects that come into play, such that the singularity is actually avoided.”
Sure. That what I meant and referred to Y.B. Zeldovich et al results. I was not able to see any unreasonable assumptions or math defects. In addition, to the best of my memory in V. A. Fock, “Theory of Space, Time and Gravitation” the topic is not discussed at all. By GR I mean A.Einstein theory of gravitation fields confirmed by the measurements and not anything else.
Bee:” It is impossible to find out whether there is a singularity behind a horizon.”
What is impossible to find out empirically directly or indirectly is not physics.
Bee:” Black holes are just the most plausible explanation for these observations and they fit very well into our theories.”
I believe that there exist unique consistent QG theory and you didn’t find it yet. All rest is the necessary intermediate models. BH I consider the artificial and irrelevant math construct which is not only follow somehow from GR but contradict it as was clearly demonstrated in numerous scientific publications.
I apologize for intervention. I didn’t follow discussion here and consider the question of BH production at the LHC nonsense. With your permission I would like to quit.
Regards, Dany.
Hi Dany,
ReplyDeleteI have no idea what you're trying to say. GR clearly has black holes as solution. You can not remove them "by the proper choice of the coordinate system (ref frame)" as you write. What you can remove by changing the coordinate system is the singularity that the metric in the Schwarzschild coordinate system has at the horizon. This singularity is not physical but an artifact of the coordinate system. What you can not remove is the singularity inside, and the horizon is a trapped surface no matter what coordinates you're working with (it's a global feature).
You are permitted to quit.
Best,
B.
Hi Bee:
ReplyDeleteHere's that book I referenced:
"Black Holes" by John G. Taylor, Professor of Mathematics at King College, University of London, copyrighted 1973 [ISBN: 0-380-00327-9]; [Library of US Congress Catalog Card Number: 73-20572]
John got himself in trouble a few years later when he started speculating about the 'occult' after having had a run-in with Uri Geller; and I believe he lost a lot of credibility as a result.
However, he wrote this book before that run-in, and he gives good acknowledgements, which I quote:
"This book owes its inspiration to the work of many scientists over several decades, who have been trying so hard to unravel mysteries of the black hole and its relevance to the universe in which we live. Naturally enough the work is most indebted to Albert Einstein, the father of relativity. Then come the pioneers who tried to discover the implications of Einstein's monumental work - Schwarschild, Landau, Chandrasekhar, Oppenheimer, Volkov, Server and many others. Over the last decade the black hole, and what it stands for, has been especially probed by John Wheeler, ably assisted by the penetrating work of Penrose, Thorne, Misner, Hawking, Carter, Gibbons, Hoyle, Zeldovitch, Novikov, Ruffini, Ciama, Israel and many others too numerous to mention. To all of these I acknowledge my debt, and especially to my colleagues Chris Isham, David Robinson, Paul Davies, Dennis Sciama and Roger Penrose for very helpful discussions on gravity, black holes and cosmology. Above all, I would like to thank my good friend Ates Orga for his continued advice during the writing of this book."
The book was written for a lay audience. However, it discusses interesting topics such as primoridal black holes and a lower mass limit for them, and even discusses Earth's movement relative to the cosmic microwave background ["One remarkable thing that the big bang should allow us to do is to measure very accurately our earth's speed with respect to the rest of the universe. For if our globe is moving through the background radiation this should appear hotter in the direction of our movement, and cooler in the opposite direction, by the Doppler shift. We should be able to observe this effect as an anisotropy in the background radiation; it should single out our direction of motion." That effect was later verified as a slight anisotropy in the otherwise relatively isotropic background. [Note: the slight 'dimpling' anistropies discovered by COBE are much smaller in effect [and might correlate to impositions by Milky Way effects by some estimates].
In any event, I'm sure you know much of the physics of this already, but just to let you know that black hole physics has a long and venerable history, and it is not surprising to me that Hawking et al. were talking about primordial black holes in 1974, since it was already in the lay literature in 1973.
Of course, I believe all of that was before your time -- i.e. you were not yet visiting on this planet as of then, though please correct me if I'm wrong about that.
Regards,
Walter L. Wagner
The GLAST satellite is a gamma ray observatory and might be capable of detecting "Hawking Radiation" from presumptive evaporating microblackholes, which is one of the projected search features. If so, then it might verify the existence of "Hawking Radiation".
ReplyDelete"The GLAST spacecraft rolled out from the Astrotech processing facility to Launch Pad 17-B over the weekend. The spacecraft was installed Friday into the payload transportation canister in preparation for transfer to the pad. Earlier in the week, workers lowered the GLAST spacecraft on to the payload attach fitting. The fitting will be used to join the spacecraft to the Delta II rocket that will carry it to space.
Liftoff is set for no earlier than June 3 during a window that runs from 11:45 a.m. to 1:40 p.m. EDT."
From NASA's web page.
Walter L. Wagner
Hi again, Bee.
ReplyDeleteI'm just curious if you know of this paper:
http://arxiv.org/abs/hep-ph/0111052
I can't quite understand the abstract, but is it saying MBHs may not evaporate as quickly as thought? If I'm wrong, please forgive me, I have no knowledge in the area.
Also, on the subject of stable MBHs, if one was produced that escaped the earth, would it be a problem if the sun captured it? Or does the cosmic ray argument take care of this?
Thanks again.
-Nick
Hi Walter,
ReplyDelete“Here's that book I referenced:”
"Black Holes" by John G. Taylor, Professor of Mathematics at King College, University of London, copyrighted 1973 [ISBN: 0-380-00327-9]; [Library of US Congress Catalog Card Number: 73-20572]”
It seems you forgot to give the full title of the book which is "Black Holes: The End of the Universe?" It also appears your Dr, Taylor has a bit a flair for the sensational. You are correct that it was one of the first books written on the topic and thankfully not the last word on the subject. What I would call the first serious book (for the general reader) written on the topic is [Black Holes and Warped Spacetime-William J. Kaufmann III-Bantam Books-1979]. My copy was the first available in paper back published in 1980 and does include a full discussion a about primordial black holes.
Best,
Phil
Hi Nick,
ReplyDeleteI'm just curious if you know of this paper?
Looking at the list of authors, I hope that she knows it ;-)
Cheers, M.
Hi Nick,
ReplyDeleteYeah, as M pointed out, I have heard of this paper. Since we're talking about the LHC though, this one might be more appropriate.
And yes, it says the MBHs wouldn't evaporate as fast as suggested by integrating over Hawking's thermal spectrum all the way down to the new fundamental scale. The reason is that Hawking's calculation is for large (astrophysical) holes, in which case you can neglect that the energy of an emitted particle lowers the mass of the remaining black hole. Not so if the holes are very small, and their mass becomes comparable to the energy of the outgoing particles. In this case you have to change the entropy of the remaining black hole and use the microcanonical ensemble. Details are in the paper. You find then that the spectrum isn't exactly thermal anymore. I couldn't find an analytical expression, but you can integrate the resulting mass-loss (or its inverse rspt.) to get the life-time. Turns out, it can be by a factor 100 larger than in the usual scenario. Note that the mass-loss ratio dM/dt diverges for M -> 0 if you apply Hawking's radiation all the way down, this isn't physical and doesn't make sense. If you use the appropriate thermodynamical ensemble, the divergence is no longer present.
This then means the MBHs can live (depending on the number of dimensions) 10^-21 seconds instead of 10^-23. Doesn't make a big difference for the question whether they can swallow the earth (the title with 'quasi-stable' wasn't my idea), but makes a difference for the particle collision since they can potentially move around while decaying.
Best,
B.
Phil:
ReplyDeleteSorry, I didn't check Antiqbooks for it. I have the paperback, and the cover is different, and reads from top to bottom as:
"BLACK HOLES THE GREAT INTERNATIONAL BESTSELLER! THE BIZARRE, UNBELIEVABLE, TRUE STORY OF THE MOST DESTRUCTIVE FORCE IN SPACE - AND ITS THREAT OF DOOM FOR ALL MANKKIND BY JOHN B. TAYLOR THE END OF THE UNIVERSE?" [different size type, with "Black Holes" largest, "The End of the Universe" second largest and found within the point of a questionmark that surrounds the words Black Holes
I doubt that John Tayor wrote the cover, and it was written to make it a best-seller.
And, he is not 'my' John Taylor. As a starting point, the book, is quite good considering when it was written. It covers lots of aspects of big bang theory, though some of the numbers are somewhat off [e.g. the cosmic microwave backround is reported as being 3 K, rather than the more current reporting of 2.7 K, etc.]
Bee:
Whether a microblackhole lives 10^-21 or 10^-23 seconds makes no difference in detection. They will still be observed as decaying at the 'point of creation', since they cannot move faster that 10^13 mm/second, the approximate speed of light. Even travelling at relativistic speed, they would still budge less than 10^-8 millimeters before decaying if their decay were delayed slightly as you explained. However, if they don't decay ...
Regards,
Walter L. Wagner
Bee writes: "...black hole does not lose energy because matter falls into it. ...I dislike the explanation with Hawking-evaporation from particle pairs at the horizon for exactly this reason..."
ReplyDeleteThe Wikipedia article on Hawking Radiation uses the following clearly fallacious argument since 2006. An argument that implies the existence of a yet undiscovered fundamental force of "anti-energy" or "negative energy".
"...vacuum fluctuations cause a particle-antiparticle pair to appear close to the event horizon of a black hole. One of the pair falls into the black hole whilst the other escapes. In order to preserve total energy, the particle that fell into the black hole must have had a negative energy (with respect to an observer far away from the black hole). By this process the black hole loses mass, and to an outside observer it would appear that the black hole has just emitted a particle."
The wikipedia article originally used the concept of tunneling:
"One of the pair falls into the black hole whilst the other escapes. In order to fill the energy 'hole' left by the pair's spontaneous creation, energy tunnels out of the black hole and across the event horizon."
In that argument, double the amount of energy that entered the black hole would have to "tunnel out" in order to negate the energy that entered the black hole and to balance the created particle that radiated.
Unless the black hole gained energy, then no negative energy nor tunneling is required. But that might require the existence of dark energy to account for the particle creation, and dark energy is still just a theory also, but gaining acceptance.
JT
Correction: In previous post I incorrectly referred to Rb87 instead of Rb85 as having resulted in an implosion beyond detection.
Hi Walter,
ReplyDelete“I doubt that John Tayor wrote the cover, and it was written to make it a best-seller.”
True as the old saying goes “you can’t judge a book by its cover”. That said how about we judge a book by its content or in this case table of contents and perhaps compare it with one that gives the subject a more serious treatment. First “Black Holes: The End of the Universe?”:
1. Worship of the Unknowable
2. The Inexplicable
3. The Optimists
4. The Black Hole Appears
5. Cannibals at Large
6. Taming Black Holes
7. Inside the Unknown
8. A New Start
9. In the Beginning
10. Achieving the Impossible Marriage
11. The Inevitable End
12. The Immortals
13. The Implications for Man
Now the Kaufamann book I spoke of “Black Hole and Warped Spacetime”
1. The Evolution of Stars
2. Stardeath and White Dwarfs
3. Supernovas and Neutron Stars
4. The Meaning of Warped Spacetime
5. The Structure of Black Holes
6. Exotic Properties of Black Holes
7. The Search for Black Holes
8. Exploring the Cosmos
9. Quasars and Supermassive Black Holes
10. Cosmology and the Final Black Hole
11. Primordial Black Holes
I would agree that John Taylor wrote this book to be a best seller yet Kaufmann wrote his and many after for a different purpose in mind and that was to have it to be good science, properly explained.
Best,
Phil
Hi Walter,
ReplyDeleteYes, this is correct. It was somewhat sloppy to say they move around. What I meant so express is just that one can ask whether it makes a difference to have exactly thermal Hawking or some deviation from it. Turns out, no it doesn't make a big difference, for one the deviations are too small, but also because the LHC is a hadron collider, so the pdfs come in everywhere. Anyway, I like the micro canonical spectrum better for the simple reason that the divergence for M->0 is gone. Best,
B.
Hi JTanker,
ReplyDeleteI didn't write the Wikipedia article, and I don't know who did. I don't even know what exactly your question is. I have repeated now roughly ten times one does not need any particles of negative energy for the Hawking effect. You have a black hole with mass M. It emits an energy E. The remaining mass of the black hole is M-E. You can write that as M+(-E) if you wish, but this still doesn't make negative energy particles necessary. For this you'd have to succeed in emitting an energy E > M, such that the remainder is negative. I don't know of anybody who ever argued this would be the case.
Best,
B.
Phil:
ReplyDeleteBy the time that "your" Bill Kaufmann got around to writing his book, six years had elapsed since John Taylor's book had been copyrighted.
I believe they were also writing for a different target audience, as well.
However, I do not believe that Taylor was writing 'bad science', but rather in certain areas he strayed from an in-depth understanding which no one then yet had, not even your Bill Kaufmann [who wasn't mature enough yet to tackle the subject].
I don't believe that any of the ideas expressed by Taylor were unique to him - - rather they were his summation of conversations and science articles then available, made 'palatable' to as wide an audience as possible.
I certainly do not 'agree' with everything Taylor wrote. However, the only reason I even mentioned that book was to show Bee that Hawking's ideas were already then being widely discussed, and that the concept of black holes was already being widely disseminated to a broad audience - - not to assert that his book is the final word on black holes.
As mentioned, I found much of the then speculation to be exactly as science subsequently confirmed, such as the speculation that a dipole anisotropy should exist in the CMB [which was later found], that a super-massive black hole was at the center of many galaxies [confirmed for our Milky Way based on orbital speeds of stars at our galaxy's center]. I consider those ideas which were, at the time, unproven, to be a very good indicator of his efforts to make his book as factually correct as possible, while appealing to such a wide audience. Of course, he did not succeed in each and every area, but I'd have to write an annotation of the entire book to show where he was right and where he was wrong, which I'm not going to do here.
He even speculated that science might someday stray and create a small black hole, which he believed would be fatal to mankind. He speculated that it would be someone intent on evil who would so such. He only briefly mentioned the topic, and did not mention either fixed-target or collider accelerators as a possible source.
The book itself is well-dated, in that it makes reference to the first moon landing which, at that time, was only four years earlier, which is exactly as he mentioned. He then speculated broadly that in the not-quite-30 years since the invention of the A-bomb [1945] to the then-present [1973] science had advanced tremendously [satellites, moon-landings, DNA discovery, etc.], and he believed it might be possible that in the then-ensuing 30 years [until 2003] additional great strides might be made.
So, now that we've had this brief segue, we can turn the topic back over to the speculation as to whether Hawking's idea of evaporating black holes [not mentioned by Taylor; likely because Hawking didn't publish it until the following year, 1974] is valid.
For my part, I would like to wait for the results of the GLAST, currently set to launch June 3, 2008, to see whether we can establish the existence of "Hawking Radiation".
Walter L. Wagner
Hmmm.... Calorimetric valuations of luminosities, and what was Joe Kapusta saying about "alien communication possibilities?"
ReplyDeleteIt's a new way in which we force new versions of, "the mapping of our universe."
Perceptions and valuations of the universe typically then reveal the value of "time dissipation" according to these calculations? "IN relation to our sun" and the lifetime of this universe, how so then the values of any possible creation in terms of the micro-world?
I know you said it before so I'll have to look , but then it would just be as easy to give a comparative response again for clarity, just so we are not all becoming delusional Walter
Enquiring minds would like to know?:)
Hi Walter,
ReplyDelete“I believe they were also writing for a different target audience, as well.”
“However, I do not believe that Taylor was writing 'bad science', but rather in certain areas he strayed from an in-depth understanding which no one then yet had”
"So, now that we've had this brief segue, we can turn the topic back over to the speculation as to whether Hawking's idea of evaporating black holes …..”
As is demonstrated this all comes down to what you believe and also evident that this cannot be altered by augment formed of reason; I therefore see little point or utility in continuing a discussion which from the start is fruitless in terms of the criteria you hold, since it is clear what is important is only what you believe.
Regards,
Phil
Hi Bee
ReplyDeleteI have been following the LHC for about a month and a half now. I know that the safety arguments are solid, but I was just curious about one thing: Hasanuddin, who is advancing a model that says the LHC could create stable MBHs, has stated on his blog that LHC collisions are more dangerous than cosmic ray collisions because "dogpiling will occur." I have skimmed his model and seen many arguments against it, so I think it is rubbish, but I want to know more about this "dogpiling" and whether or not it is true:
Hasanuddin wrote: ""I’ll admit that a lone cosmic ray particle striking the Earth will have more energy than two lone protons smashing head-on—but that isn’t what will happen inside of LHC, is it? LHC is designed to smash packets of 10,000,000,000 protons into packets of 10,000,000,000 in one tight spot. Using “all-things-being-equal” blinders to ignore to cumulative effects of the 9,999,999,999 other potential collisions of each packet will skew the overall estimate making LHC seem benign and harmless. Collision of packets will not occur as a one-time event either, will they? They will happen repetitively in very quick succession, which will allow for dogpiling. Is any of this similar to a cosmic ray striking the Earth—no."
http://science-community.sciam.com/blog-entry/Hasanuddins-Blog/Stop-Presses-Actually-Stopping-Presses/5800000321&start=15
I personally do not hope I am not disturbing you. I simply would like to hear an answer from an expert, since I know little about the situation.
Actually, Hasanuddin posted a comment on your blog about his model:
ReplyDeletehttp://backreaction.blogspot.com/2007/07/lhc-at-nature-insight.html#c5813482062560311948
Hi Tayman,
ReplyDeleteI have no idea what 'dogpiling' is supposed to be. Of course the LHC doesn't just hit single protons into each other, that's why to get a number of events per time interval we multiply the cross-section with the luminosity. I can't quite recall the luminosity for the LHC at 14 TeV but I think it is planned to reach something like 10^33/cm^2/s. I have no clue why that person thinks therefore black holes at the LHC are more dangerous. It's not like the decay products of one collision linger around in the middle of the beam axis waiting for the next proton. Maybe he'd want to clarify what exactly he means with 'one tight spot,' and actually calculate the probability that produced black holes meet. And then show that they don't decay, but we've already had that. Best,
B.
You can't produce Black Holes at the LHC because I own the copyright The Black Hole . I Designed The Black Hole, I know you might think thats stupid, but the universe is stupid. Although not as stupid as me, only a fool would create an object he can never escape from; thats me "The fool!"
ReplyDelete"Here is a section from wikipedia on the fool :- The Fool is the spirit in search of experience. He represents the mystical cleverness bereft of reason within us, the childlike ability to tune into the inner workings of the world. The sun shining behind him represents the divine nature of the Fool's wisdom and exuberence. On his back are all the possessions he might need. In his hand there is a flower, showing his appreciation of beauty. He is frequently accompanied by a dog, sometimes seen as his animal desires, sometimes as the call of the "real world", nipping at his heels and distracting him. He is seemingly unconcerned that he is standing on a precipice, apparently about to leap, engaged in the supremest act of idiocy or trust.
The number 0 is a perfect significator for the Fool, which can become anything when he reaches his destination. Zero plus anything equals the same thing. Zero times anything equals zero.[5] Zero is nothing, a lack of hard substance, and as such it may reflect a non-issue or lack of cohesiveness for the subject at hand."
Black holes are sensitive creatures they will never form under all them wires and all that metal, Black holes like to be free!
Hi,
ReplyDeleteActually, I think Hasanuddin thinks that matter-matter collisions will attract each other. His new model claims that matter and antimatter repel each other gravitationally, and matter-matter attracts each other. I think that he thinks that these "matter collisions" at the LHC will clump together, and reach high enough energy that a stable MBH will be formed (which is also predicted by his model).
http://science-community.sciam.com/blog-entry/Hasanuddins-Blog/Stop-Presses-Actually-Stopping-Presses/5800000321
It's crazy, really.
Yes, it's crazy. Sorry, but I really don't have the time to debunk everybody's idea about what the LHC might be able to do when one doesn't know particle physics. The following doesn't have anything to do with you particular.
ReplyDelete___
Folks, I think it's about time to close this comment section, it has exceeded a length where one can have a sensible discussion. Thanks everybody for dropping in.
-B.