tag:blogger.com,1999:blog-22973357.post301072902480960253..comments2023-09-27T07:44:19.769-04:00Comments on Sabine Hossenfelder: Backreaction: Why a larger particle collider is not currently a good investmentSabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comBlogger187125tag:blogger.com,1999:blog-22973357.post-5721717769078935652019-03-13T18:00:18.555-04:002019-03-13T18:00:18.555-04:00Sabine,
yes, that's my ResearchGate Profile....Sabine, <br /><br />yes, that's my ResearchGate Profile. It tells that I work for CERN, neither as a particle- nor accelerator physicist, but in my role as a safety expert I have contacts with many scientists, engineers and technicians of the organisation. Also, I actually worked in nuclear, atomic and particle physics 25 years ago, and it's like bicycling, you don't really forget theTottohttps://www.blogger.com/profile/14663275133049157719noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-62064861875171034722019-03-13T14:56:39.342-04:002019-03-13T14:56:39.342-04:00"To state the obvious, you can equally well c..."To state the obvious, you can equally well compare total numbers."<br /><br />No, you can't. That's not how correct comparisons work.<br />You need to divide the total cost (construction+management) by the total duration in time.<br />So, any argument saying that experiment X is cheaper than experiment Y simply by looking at absolute numbers is flawed for obvious reasons.<br />Claudiohttps://www.blogger.com/profile/17853497508155197037noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-2701528446483536502019-03-13T10:11:27.367-04:002019-03-13T10:11:27.367-04:00Thomas,
Ahead, do you happen to be this Thomas Ot...Thomas,<br /><br />Ahead, do you happen to be <a href="https://www.researchgate.net/profile/Thomas_Otto5" rel="nofollow">this Thomas Otto</a> or some other one?<br /><br />I do not "disagree" with this argument, I point out that it's stupid. Of course you can divide $20 billions by whatever number of people you wish, there is nothing to disagree here. But that doesn't make it Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-65273312784414184272019-03-13T08:55:25.456-04:002019-03-13T08:55:25.456-04:00Sabine, the fact that you disagree with an argumen...Sabine, the fact that you disagree with an argument does not mean that it is invalid ("debunked").<br />Taxpayers, to whom we are in fine liable, may want to undestand how the money they handed over to the state is used, and some visual comparisons (cents per day or cappucinos per year) help in making abstract numbers understandable. I have nothing against doing the same exercise with Thomas Ottohttps://www.blogger.com/profile/03294902602188111919noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-5280680502557598082019-03-13T08:25:32.258-04:002019-03-13T08:25:32.258-04:00More powerful magnets are in the pipeline. 11T dip...More powerful magnets are in the pipeline. 11T dipoles are being built (40% increase to present LHC-standard), 16 T is the FCC baseline, and 20 T may become possible with high-temperature s.c. I wanted to express that this research will not continue if there is no motivation for it, e.g. a next collider. <br />Don't expect Siemens to spend the money to develop 8T MRI systems, when they can Tottohttps://www.blogger.com/profile/14663275133049157719noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-80427287298207205032019-03-13T02:27:45.942-04:002019-03-13T02:27:45.942-04:00Totto,
That technical personal gets trained that ...Totto,<br /><br />That technical personal gets trained that moves on to industry is an argument that can be made about any large experiment. It does not explain why a large collider in particular is the thing to build.<br /><br /><i>"Stopping this field and waiting that someine develops, out of the blue, a better accelerator (with better magnets,as I read above) is not working..."</i><Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-4490422460273557262019-03-13T02:23:52.816-04:002019-03-13T02:23:52.816-04:00Ah, yes, the "it's only so-and-so many ce...Ah, yes, the "it's only so-and-so many cents per day per person" argument. You realize you can do the same exercise with literally any other expense and it doesn't make it any cheaper? Also, I have debunked this silly argument dozens of times already. Try harder.Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-41963731808893147432019-03-12T07:49:58.705-04:002019-03-12T07:49:58.705-04:00Is anybody here aware of the spin-offs of a large ...Is anybody here aware of the spin-offs of a large accelerator-based research institute ? <br />- CERN trains hundreds of technical personnel per year in science and technology. After their apointments with CERN they go to industry in the member states and apply what they have learned in an international, collaborative and competitive environment. The benefits for international understandg and Tottohttps://www.blogger.com/profile/14663275133049157719noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-32768414541367217592019-03-12T07:17:03.846-04:002019-03-12T07:17:03.846-04:00The annual cost of CERN, at about 1 Billion CHF, i...The annual cost of CERN, at about 1 Billion CHF, is equal to 2 cappucinos per inhabitant of the member states. <br />The price for a new collider would not have to be paid upfront, but it woyld be built at constant budget (as did LHC and currently High-Luminosity LHC). The high spending during construction is covered by loans, which are repayed from the (constant) budget over the following years Tottohttps://www.blogger.com/profile/14663275133049157719noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-9701580773449800302019-02-21T00:17:59.284-05:002019-02-21T00:17:59.284-05:00Udi,
I mentioned ASG as an example for a solution...Udi,<br /><br />I mentioned ASG as an example for a solution to the problem to explain that what I am talking about is an actual problem (the inability to calculate what happens) and not a philosophical problem (like naturalness). <br /><br />I did not say, not here and not elsewhere, that I can calculate the probability of finding quantum gravity at the FCC using perturbative quantum gravity. Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-8619241239453528332019-02-20T22:24:01.769-05:002019-02-20T22:24:01.769-05:00You are the one that brought up ASG. In any case, ...You are the one that brought up ASG. In any case, it seems that in ASG the counter terms are not set to zero. Instead, it is assumed that a fixed-point exists and that the counter terms would flow to that fixed-point.<br /><br />I think that we both agree that it is wrong to assume that nature would behave according to our plans, whether it is naturalness or a fixed-point. What I am claiming is Udi Fuchshttps://www.blogger.com/profile/02529460830838964526noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-24004161141230087942019-02-18T11:20:47.588-05:002019-02-18T11:20:47.588-05:00"peter shor
"... and (b) it is indeed t..."peter shor<br /><br />"... and (b) it is indeed technologically possible to increase the sensitivity so that it will see black hole mergers, which we know exist."<br /><br /> That could be a good point, provided one specifies that if LIGO, VIRGO and most of all all future upgrades will be able to get to better sensitivities it will be thanks to research carried out for HEP roberto kersevanhttps://www.blogger.com/profile/08293551219458418162noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-22821174177660329722019-02-18T11:17:12.167-05:002019-02-18T11:17:12.167-05:00@sabine
"More seriously, what do you think yo...@sabine<br />"More seriously, what do you think you will achieve with this. Suppose you get funding for the and in 30 years people will come and ask, so now what is ? What do you want to tell them?"<br /><br /> So, sabine, let's open a new blog to take down and de-fund ALL EU public research on cancer... 'cause it has been funded during way more than 30 years... for amounts roberto kersevanhttps://www.blogger.com/profile/08293551219458418162noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-4856910380454427732019-02-18T00:50:15.337-05:002019-02-18T00:50:15.337-05:00Udi, I am the wrong person to ask about the detail...Udi, I am the wrong person to ask about the details, sorry. But there is a huge literature on the topic that I am sure you can find without my help. Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-87999668463080486262019-02-18T00:02:06.267-05:002019-02-18T00:02:06.267-05:00The expansion in this ASG paper is in the number o...The expansion in this ASG paper is in the number of derivatives, so it is the same expansion I am talking about.<br /><br />Specifically, to second order he calculates both R^2 terms. For some reason he skips third order terms and shows only one term at fourth order. It does not make any sense to me.<br /><br />If I understand correctly, the fix-point should be non-perturbative. Finding a Udi Fuchshttps://www.blogger.com/profile/02529460830838964526noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-28731415562496461712019-02-17T00:28:52.245-05:002019-02-17T00:28:52.245-05:00Udi,
You are right about QED of course, I meant r...Udi,<br /><br />You are right about QED of course, I meant renormalizable, not UV complete, sorry.<br /><br />I'm not entirely sure how to translate the ASG calculation into the language of the perturbative expansion because they use a different expansion so the (running) couplings they deal with may not be the same as the ones you have in mind. <br /><br />In any case, no they don't justSabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-32156007994270941142019-02-16T13:38:21.677-05:002019-02-16T13:38:21.677-05:00Sabine wrote:
"That you do not know when tho...Sabine wrote:<br /><br />"That you do not know when those terms become relevant does not help you make predictions is what I am saying."<br /><br />That is also what I am saying. Neither of us can make any prediction about what the next collider will find. Personally, I am very curious to find out, even if it might be a null result.<br /><br />Regarding QED. It is not a UV-complete Udi Fuchshttps://www.blogger.com/profile/02529460830838964526noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-30330230114146842832019-02-15T23:57:57.236-05:002019-02-15T23:57:57.236-05:00Udi,
That you do not know when those terms become...Udi,<br /><br />That you do not know when those terms become relevant does not help you make predictions is what I am saying. <br /><br />With QED you could say it's a problem of doing the calculation, you already have a UV-complete theory. For quantum gravity we don't even have the theory. <br /><br />Think of Asymptotically Safe Gravity. It solves the problem by telling you what the Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-30676238610275827432019-02-15T18:34:29.475-05:002019-02-15T18:34:29.475-05:00Pascal wrote:
"I did not rephrase anything. ...Pascal wrote:<br /><br />"I did not rephrase anything. I did not use quotes to make it look like a citation. That is something you just invented."<br /><br />I didn't say that you misquoted someone, I said that you rephrased. You took some comment that maybe you heard someone said somewhere, you rephrased it and then you blame an entire group of people of having the same opinion. Udi Fuchshttps://www.blogger.com/profile/02529460830838964526noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-54768832064149375252019-02-15T18:19:09.759-05:002019-02-15T18:19:09.759-05:00I think that I understand our confusion. I am gues...I think that I understand our confusion. I am guessing that you are referring to the fact that perturbatively quantized GR is strongly coupled at Planck energies, and therefore the perturbative expansion breaks down.<br /><br />This has nothing to do with GR being non-renormalizable. QED is normalizable, and still its pertubartive expansion breaks down at the Landau pole.<br /><br />I am talking Udi Fuchshttps://www.blogger.com/profile/02529460830838964526noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-4518975473168528962019-02-15T07:56:46.898-05:002019-02-15T07:56:46.898-05:00Pascal, Udi,
"Comments can get deleted by th...Pascal, Udi,<br /><br /><i>"Comments can get deleted by their authors and with this, attached direct replies."</i><br /><br />As someone kindly checked for me, what you say is not correct. If an author deletes a comment, this will leave an empty relic comment that says "comment deleted by author". This will not remove responses to the (no longer existing) comment. <br /><br />Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-66350810836400843282019-02-15T06:59:52.002-05:002019-02-15T06:59:52.002-05:00"Suppose you get funding for the FCC and in 3...<i>"Suppose you get funding for the FCC and in 30 years people will come and ask, so now what is the origin of the universe? What do you want to tell them?"</i><br /><br />The common answer is - by then I'd have retired. Not my problem.Arunhttps://www.blogger.com/profile/03451666670728177970noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-5657314206827165032019-02-14T22:50:00.016-05:002019-02-14T22:50:00.016-05:00I don't know if Einstein would have anticipate...I don't know if Einstein would have anticipated engineering applications for general relativity. They only exist because of the communications satellite, which was first conceived thirty years after Einstein's theory. Einstein didn't even live to see Sputnik. <br /><br />Any "daily life" impact of supersymmetry or string theory is likely to come, not from engineering that Mitchellhttps://www.blogger.com/profile/10768655514143252049noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-90613648751121195362019-02-14T11:00:11.040-05:002019-02-14T11:00:11.040-05:00Fx,
It is correct that I am not an expert on the ...Fx,<br /><br />It is correct that I am not an expert on the recent developments in particle physics. Neither did I pretend to be one. Your questioning my expertise rather than my argument is also irrelevant to the discussion and constitutes an ad hominem attack. <br /><br /><i>"it is extremely arrogant to come here and tell us our field is not promising"</i><br /><br />I did not say Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-50211220266372369982019-02-14T09:50:44.839-05:002019-02-14T09:50:44.839-05:00Hi Sabine,
I think we are slowly going in circles...Hi Sabine,<br /><br />I think we are slowly going in circles so apologies if I do not address all of your points.<br /><br />Believe it or not I am not personally offended or angry or anything. But you say that you have thought more about my own field than me or my colleagues, yet I don't see anywhere any indication that you have any expertise in modern particle physics or even have anything Fxhttps://www.blogger.com/profile/07265035195445914376noreply@blogger.com