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Monday, June 30, 2008

Science Mugs

On Friday I came across Corie Lok's blog who announces the "Nerdiest Science Mug Competition" and offers a DNA strand with the names of faculty members. Brian Clegg adds a global warming mug, and Bob O'Hara contributes a mug from the Metapopulation Research Group (website). I can't quite keep up with so much nerdiness, but I found my mug from the String Pheno 2004 in my husband's kitchen. Here it is:



Looks like a black hole but if one fills in hot coffee it reveals...



A Calabi-Yau manifold. (Seems to be essentially the same picture as this.) And here is the backside, just for completeness.




My favourite mug is actually my PI mug, black and stylish.

So what's your nerdy mug? (Blogger doesn't allow images in the comments but you can leave links.)

Sunday, June 29, 2008

This and That

Saturday, June 28, 2008

Alice and Bob

Alice: You are late. How was your day?

Bob: Sorry honey, I had to wait for t = infinity, it took forever.

Alice: Thanks for asking, my day was perfect, I was thrown into the black hole three times.

Bob: At least you get to see something, you never tell me...

Alice: You know I can't.

Bob: What am I supposed to wear?

Alice: I took out the black suit and the shirt, it's in the bedroom.

Bob: I really hope they get this information loss stuff sorted out at some point, it's terribly annoying.

Alice: I hear we'll be back to Special Relativity next week.

Bob: Oh, really? The simultaneity again? How long will it take until they've understood it!

Alice: No, something about the clicks of the Unruh detector.

Bob: Humm. Am I supposed to wear a tie?

Alice: Well, I think the family would appreciate if you'd show some respect for my ex.

Cat: Meeow.

Bob: Oh no. Did they send more packages?

Alice: Oh yes. Seems you got the dead one, I left it downstairs.

Bob: Doesn't it ever cross their mind that disposing all these dead cats isn't so easy? The neighbors already talk, I heard them last week...

Alice: You can't wear sneakers to a funeral.

Bob: Well, he doesn't care any longer, does he?

Alice: Do me the favor, it's a tragic story and I don't want anybody to think we're not serious.

Bob: Tragic? Well, he shouldn't have shot his grandfather!

Alice: We don't even know that. Do we really have to go through this again?

Bob: Well, if we'd know whether he made it to the other side of the wormhole, you must know...

Alice: You know I can't tell you!

Bob: Yah yah! Cosmic cencorship! But it's unproved!

Alice: Well, one never knows, I don't want to cause us problems. Don't you see I'm just doing this for us!

Bob: Anyway. Will Fido be there?

Alice: Don't think so. Last time we talked he had a problem with a Kerr-Newman black hole.

Bob: Good, good. Let's go. I really think we could need a vacation.

Alice: We could ask for a different branch of the multiverse tomorrow.

Cat: Meeow.

Thursday, June 26, 2008

Seminar in Heidelberg

This lovely old villa is the Insitute for Theoretical Physics in Heidelberg where I gave a seminar yesterday.


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A very warm and welcoming place with lots of wood inside, a garden and nice people! Here are three friendly faces, from left to right: Carlo Ewerz, Eduard Thommes and Thomas Dent (Thomas D you might know from the occasional comment at this blog).


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The photo was taken from a balcony on the upper floor with a great view on the city and the river Neckar. If you peer really hard you can see the Heidelberg castle in the background.

Tuesday, June 24, 2008

The Black Hole Information Loss Paradox

Prologue

I am constantly fighting information loss. Most importantly, there seems to get a lot of information lost in emails I write if those exceed one paragraph. What comes back then is stochastically distributed words that are uncorrelated with what I wrote. Anyway, as I had to realize yesterday, an inbox can also turn into a black hole if IT moves the folders but doesn't tell you how to reconfigure the ssh tunnel.


Not the Paradox

So, what is the black hole information loss paradox? The evolution laws in quantum mechanics are time-reversal invariant. (That does not include the measurement process, which does set limits to our knowledge). Initial states evolve into final states, the evolution is given by a Hamiltonian and is unitary. You can turn it back around. If you start with something it will go into something with probability one. The evolution is a one-to-one map. Unitarity is a fundamental property of quantum mechanics.

Now consider you have some matter distribution (e.g. a pressureless gas) and let it collapse (for simplicity assume it is spherically symmetric). That what you need to specify the precise state I will call information. The collapsing matter forms a horizon and becomes a black hole. The black hole no-hair theorem says that a black hole can carry only three parameters: mass, angular momentum, and electric charge. After the collapsing matter has settled down, this is the only information you can get from examining it. What happened to all the other information of your gas? All the details of that initial state?

Well, you could say, it's inside the black hole. So, no, collapse and formation of a horizon is not the information loss problem. You could say, the information still exists, but we are just disconnected from it. What's the problem with that? As long as my inbox still exists at least somewhere, that's okay, even if I can't access it.

The Paradox

But Hawking tells us black holes emit radiation, and this radiation is thermal. It is purely thermal, completely random, does not contain any information except its temperature. That is in contrast to e.g. the radiation of the sun. Which is for all practical purposes also thermal, but it does contain information 'in principle'. If you'd throw your bag of gas into the sun and you waited long enough you could 'in principle' extract its details again from the sun's radiation. Not so for the black hole. There is nothing to learn from the black hole's radiation.

Still you could say, well, if no information comes out, then it just stays inside.

But if Hawking is right, and the black hole radiates, then it loses mass. And eventually it is completely evaporated. There is nowhere left for the information to remain. The only thing that you have in the final state is that thermal radiation distributed over space. One could say then, well, black hole formation just is not time-reversal invariant. A singularity forms. A singularity is an attractor, whatever you started with it is always equally singular. There is no one-to-one map. Why is that a problem?

Well, the black hole formation could have happened for anything that forms or later falls into the black hole, and we know stuff behaves according to quantum mechanics. We have tested that experimentally uncountably many times. But if you consider an initial quantum state for the black hole, then no matter what precisely it was, the result is always thermal radiation, determined solely by the total mass, charge, and angular momentum. If you look at the final state, you can't trace it back to the initial state. It's not a one-to-one map. The evolution is not unitary, in conflict with the laws of quantum mechanics.

And that's the problem. The paradox. The apparent disagreement between general relativity and the laws of quantum mechanics. Hundreds, if not thousands of papers have been written about it since the solution to this paradox can be a key to our understanding of quantum gravity - whatever that theory looks like it should be able to resolve the problem.

Solution Attempts

A crucial aspect of this problem is that evaporating black holes are to excellent approximation classical objects for a very long time. Quantum gravity only can become important in the very late stages of the evaporation, then when the curvature comes in the Planckian regime, which happens only when the black hole's mass is about Planck mass (or its diameter of the order Planck length respectively.) Quantum gravitational effects thus can only influence the radiation in the last stages.

Various approaches have been tried to solve the problem, all have advantages and disadvantages (this is likely an incomplete list):
  • Solution: The evolution just is not unitary and information is indeed lost.

    Problem: This is not only unappealing because it requires us to rethink how quantum mechanics works, it also leads to violations of energy conservation.

    Reading:

    Unitary Rules for Black Hole Evaporation
    Andrew Strominger,
    hep-th/9410187


  • Solution: Black hole evaporation is modified in the late stages and black holes do not completely radiate but leave behind a stable remnant of approximately Planck mass that keeps the information.

    Problem: Since the initial state that collapsed could have been anything, if the information is kept in the remnant that remnant must be able to carry an arbitrarily high amount of information. This leads you to conclude there must be an in principle infinitely large amount of black hole remnants with the same mass that are however different since they have different information content. This in turn results in the possibility to pair produce these objects infinitely in any arbitrarily complicated process where the energy is high enough. Even if the probability for the production of a single remnant is arbitrarily small, if there are infinitely many of them, you will still produce them. You could also emit them in black hole radiation itself: The high energy tail of the black hole spectrum might be exponentially suppressed, but if multiplied with infinity, black holes of arbitrary mass would decay instantaneously.

    Reading:
    Comments on information loss and remnants
    S.B. Giddings,
    hep-th/9310101

    Constraints on Black Hole Remnants
    S.B. Giddings,
    hep-th/9304027

    Trouble For Remnants
    Leonard Susskind,
    hep-th/9501106

  • Solution: The information comes out with the radiation in the very late stages.

    Problem: Then you have only very little energy left to carry all that information, which could have been arbitrarily much. This means per each unit of information you have a very small amount of energy to emit it which takes a long time, and you can't emit it simultaneously because if the wavefunctions overlap they'd be correlated. So that last stages would last very long (the more information needs to go out the longer) leading to quasi-stable black holes which cause essentially the same problems as the remnants of the previous point (their mass spectrum is not exactly degenerated but almost). Besides this, one would like to have an exact mechanism for how that happens.

    Reading:

    Do Black Holes Destroy Information?
    John Preskill,
    hep-th/9209058

  • Solution: Black holes evaporate completely but while so have formed a causally completely disconnected baby universe in which the information survives.

    Problem: Requires you to believe in a multiverse in whose totality information is conserved, though locally, in our universe, it isn't.

    Reading:
    A Possible Resolution of the Black Hole Information Puzzle
    Joseph Polchinski and Andrew Strominger,
    hep-th/9407008


  • Solution: Since the AdS/CFT conjecture relates black holes (in AdS space) to a quantum theory one knows is unitary on the boundary, this would mean the evolution in the bulk is also unitary.

    Problem: As long as the conjecture is unproved one could equally well consider the information loss problem, if real, as a counter-example for the validity of the conjecture. (Also, I personally would find it unsatisfactory would this only work in AdS space).

    Watching:

    The Black Hole Information Paradox, Past and Future
    Joe Polchinski,
    PIRSA: 08040001

  • Solution: Black holes have quantum hair that is not taken into account in the no-hair theorem.

    Problem: Since the black hole can carry arbitrarily much information, one needs arbitrarily many quantum numbers to do that and a modification of our theories that can accommodate them. Why haven't we yet observed any of that? (Also, it's not clear to me how one would know that the black hole always carries enough of these new quantum numbers.)

    Reading:

    Quantum Hair on Black Holes
    Sidney Coleman, John Preskill and Frank Wilczek,
    hep-th/9201059

  • Solution: Other - There are no black holes / There is no Hawking radiation / There is no spoon, ie we live in a virtual reality and this paradox was created just for the amusement of our programmer.

    Problem: Possible but far fetched.

    Reading:

    The bleakness of reality.

Why I voted "No for other reasons"

From how I stated the problem above, it hopefully became clear why I think the problem is the singularity, not the horizon. The horizon is where information becomes inaccessible, but the singularity is where it gets lost. That's more or less by definition what a singularity is all about. The singularity is where the evolution becomes non-deterministic, where it can't be uniquely continued, it's where all initial states are crunched into the same divergence - already classically. Unlike the classical case however, here we have a scenario where the final state is without singularity again. Thus, the slicing has somehow to pass the singularity*.

But it is generally expected that some version of quantum gravity resolves the singularity and smoothens it out. Then, there is as far as I can see no reason why the evolution should be non-deterministic if the black hole eventually completely evaporates. If there is no slice on which initially different states run together, evolution from the initial to the final state has to be a one-to-one map. Determinism isn't sufficient, but necessary for unitarity. Either way, even if avoiding the singularity would imply unitarity, the problem then was not why, but how the information comes out.

Vaguely related reading:

Black hole evaporation: A paradigm
Abhay Ashtekar and Martin Bojowald, gr-qc/0504029

The paper mentioned in the previos post by Dr. Who (Horowitz and Maldacena, hep-th/0310281) tackles this problem with the uniqueness of the state by imposing a final state boundary condition at the singularity which effectively transfers the information in the outgoing radiation. It's an interesting paper (thanks for pointing it out!), but the solution seems to me very ad hoc.

Bottomline

The black hole information loss paradox makes for an excellent topic over which to argue, because everybody has a different favourite solution. Of course I don't believe any of the above offered solutions, and of course nobody agrees with me. Anyway, here are the preliminary results of our poll "Do Black Holes destroy Information?":

From presently 146 people who voted, the majority, 37.7%, said "No, it comes out in the radiation.". A for me surprising 25.3% said yes, black holes destroy information. 16.5% including me voted "No, for other reasons.", documenting the mentioned plurality of opinions. Again surprising for me a full 8.9% voted for the remnant solution. (Surprising because whenever I say 'remnant' I get shouted down immediately.) Also 8.9% said 'Other' which includes the quantum hair option that I forgot for the poll, and 2.7% think the information survives in a baby universe.

If you didn't yet vote, vote now! If you did, has this post change your mind?

Epilogue

The one-hour phone call to Canada to figure out how to reconfigure my email client and tunnel through to my inbox goes on my mom's bill. I had to re-download 12,442 emails, but no information got lost.


* Andrew: In the paper you mentioned by Zeh: gr-qc/0507051, he has an endstate with singularity, see Fig 1. In this case you can draw surfaces up to arbitrarily late - but finite! - times that do not reach the singularity, but this is not the relevant scenario in which the black hole is eventually completely evaporated.


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Monday, June 23, 2008

Cacti

And again I am in Germany, fighting a jetlag. School holidays just begun, everybody is talking about soccer, and today I am visiting my parents. As you might know, I lived in Arizona for a while, and some years ago I brought my mother a couple of giant-cacti seeds. (The customs officer apparently was not too worried cacti would overtake the German fauna.) My mother indeed planted the seeds and here is how the baby cacti look at age 3 years


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And that's how they look all grown up, takes a hundred years or so


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The above photo was taken in Tucson, Sabino Canyon I think. One gets kind of used to these cacti, the really large ones are called Saguaro Cacti. During winter, Tucson has a couple of nights in which temperatures can drop below freezing point. Since the water content of these plants is quite high, to prevent the smaller arms of their cacti from freezing, people cover them with clothes or paper cups. Looks quite funny.

Browsing through my old image folder I also found some nice photos of blooming cacti: here, here, here and here.

If you think this post is pointless, that's because it is.

PS: And today is our 2nd wedding anniversary!

Saturday, June 21, 2008

Black Holes at the LHC - The CERN Safety report

Earlier this year there has been a bit of confusion about potential dangers of switching on the Large Hadron Collider (LHC) at CERN. A lawsuit in Hawaii brought old fears back on the front pages of newspapers again, that the Earth may possibly be destroyed by strangelets, magnetic monopoles, instabilities of the vacuum, or black holes created in the high-energy proton-proton collisions planned at the LHC. We had discussed the actually non-existing danger posed by micro black holes in our posts Black Holes at the LHC - What can happen? and Black Holes at the LHC - again.

Yesterday, CERN has finally published the official report by the LHC Safety Assessment Group (LSAG). A CERN press release announces that the CERN Council looks forward to LHC start-up, and that the new report, updating a 2003 paper, incorporates recent experimental and observational data and confirms and strengthens the conclusion of the 2003 report that there is no cause for concern. Today's New York Times quotes from the abstract of the technical paper by Michelangelo Mangano, CERN, and Steven B. Giddings, UCSB, which is one of the pillar of the LSAG report that [...] indeed, conservative arguments based on detailed calculations and the best-available scientific knowledge, including solid astronomical data, conclude, from multiple perspectives, that there is no risk of any significance whatsoever from such black holes.

But just have a look at the report by yourself:

  • A summary of the LSAG report is available (as PDF file) in English, French, German, and Italian: The safety of the LHC / Le LHC peut être exploité en toute sécurité / Sicherheit am LHC / La sicurezza dell’LHC.

  • The actual report is the 15 pages Review of the Safety of LHC Collisions (PDF file) by John Ellis, Gian Giudice, Michelangelo Mangano, Igor Tkachev and Urs Wiedemann of the LHC Safety Assessment Group.

  • Technical details about strangelets and black holes can be found in the 11 pages Addendum on strangelets (PDF file) to the Review of the Safety of LHC Collisions, again by Ellis, Giudice, Mangano, Tkachev and Wiedemann, and in the 97 pages paper Astrophysical implications of hypothetical stable TeV-scale black holes by Steven B. Giddings and Michelangelo L. Mangano (available as preprint CERN-PH-TH/2008-025 (PDF file) and arXiv:0806.3381 [hep-ph]).

  • A review of the report and the two technical papers was prepared by the CERN Scientific Policy Committee (SPC) to provide [...] an independent opinion on the conclusions stated in those documents. SPC panel members Peter Braun-Munzinger, Matteo Cavalli-Sforza, Gerard ‘t Hooft, Bryan Webber and Fabio Zwirner came to the conclusion that they fully endorse the conclusions of the LSAG report: there is no basis for any concerns about the consequences of new particles or forms of matter that could possibly be produced at the LHC.
    This review is also available as a PDF file.


The main focus of the Giddings-Mangano paper lies on a detailed analysis of the possible creation of microscopic black holes by cosmic rays and at the LHC, and on a meticulous discussion of the potential growth mechanisms of these black holes. This analysis then allows to conclude, from the observed existence of very old and dense astronomical objects such as neutron stars, that the Earth is safe - at least from potential dangers posed by the LHC.




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Friday, June 20, 2008

Poll: Black Hole Information

I meant for some while to write a post about the black hole information loss paradox, but despite my best intentions I haven't yet come around to doing so. As a warm up, for you and me, here is a poll:



Btw, here are the results of our last poll "Does the past and the future exist in the same way as the present?" From 153 votes, 41.2% decided for "Past, present and future exist in the same sense," 29.6% for "It is only the now that exists, but neither the past nor the future." And, surprising for me, only 15% voted for "The past exists as does the present moment, but the future doesn't.". The remainder chose "Other".

Interna

When I visited PI the first time, I got a visitor information package that among other things contained the Waterloo UpTown Business and Service Directory. In this brochure I found under 'T', between 'Tea Shops' and 'Travel Agencies' the entry 'Theoretical Physics' which lists Perimeter Institute. (It's the only entry in this category.)

Yesterday I picked up the new version of that brochure, which still integrates without any fuzz Theoretical Physics with Tattoo Studios and Night Clubs. I just looked up their website: www.uptownwaterloobia.com (bia = business improvement area). Does that building shown on the header with the sentence 'An experience you'll want to come back to' look familiar? You can also search the site for businesses, where you will find the category 'Theoretical Physics' as well.

Yes, Waterloo is really a nice and welcoming place for theoretical physicists. People congratulate me on the street that Mike Lazaridis just donated another $50 Mio, and tell me how much they enjoy the public lectures. It is a very pleasant environment to work in. Meanwhile, I am trying to find a sponsor for our September conference so we can have a reception the first day. I need an estimated $1,500 as I've been told - if you have any suggestions for who might be interested in sponsoring a conference on "Science in the 21st Century", please let me know. (I applied for a grant for travel support of younger people, but even if this goes through, which I don't yet know, I probably can't use it otherwise.)

Besides this, I am going on a trip today that will imply giving some seminars and so on. I will probably be stuck in transit and jetlag for a while, so you're facing a slow time.

A nice weekend to all of you.

Thursday, June 19, 2008

Pi in a Cornfield


[Aerial image © 2008 by Lucy Pringle]

This photo shows a crop formation near Wroughton, Wiltshire, U. K., reported June 1, 2008. It is about 300 feet in diameter. The angles of the circle between the steps encode the first digits of Pi, as noted by Michael Reed. For more photos see here. For more info see here. For commentaries see here. Pretty, isn't it?

Wednesday, June 18, 2008

What is a System?

On the weekend my confusion about the whatabouts of life, the universe and everything else temporarily reached alarming proportions. Reason was that I tried to figure out what on Earth does it mean to 'fuck the system'? I have some familiarity with the four-letter word in this expression which leaves me to wonder what do we actually mean with 'system'?

Asking myself how I and most of my colleagues seem to use the word, I would have said the system is that what is described by a model (see also: Models and Theories). Then however I made the mistake of looking into the matter (e.g. in Bossel, "Systems and Models") which produced the rather abstract definition that a system is a set with elements that stand in some relation to each other, and generally has an environment that possibly provides input and absorbs output. A dictionary further explains:

    System: from Gk. systema "organized whole, body"

After I had halfways reconciled these matters, I read a book called


(it's only 90 pages), which is essentially about systems and piles, and sub-systems and supersystems, life and love and reproduction, atoms and cats, self-reflective consciousness - and then manages in one full sweep to declare capitalism an outdated model, ventures for all-volunteer armies, and finishes with proclaiming a new kind of religion "celebrating [...] the sudden synthesis of the quarks and of the wide diversity of microparticles as well as of atoms and molecules throughout the expanding reaches of cosmic space". Wow. The author certainly had a vision. And if you want to get really confused, try reading this.

Either way, this didn't quite clarify what a system is either. To maybe explain why my confusion, let me ask instead: What is not a system?

Lazlo goes and piles rubbish as an example (p.25). Systems, so he argues, change qualities with the elements added. But to a pile of rubbish you can add more rubbish, and all you get is a larger pile of rubbish. It makes only a quantitave difference, he writes, it does not change the 'system' as a whole.

Now if I think in terms of mathematical definitions I can very well understand there's things that are not systems. But if I look at the real world I can't find no example for that. Everybody who is familiar with rubbish (and as a blogger I certainly am) knows that rubbish usually doesn't just orderly add up -it can develop some dynamics on its own. The pile Lazlo discusses just reminds me of the sand-pile model, a well known example for a dynamical system with self-organized criticality. So, here it goes again, we have a 'system'. The only example I can think of where one could have, in Nature, a set of somethings without any relation (interaction) between the somethings is some sort of multiverse. The analogy to Lazlo's pile of rubbish is striking.

But if everything is a 'system' then what is it good for talking about systems? Well, the usefulness of thinking in terms of systems is one of classification. One can have varios forms of systems with specific properties. Open and closed systems. Systems in equilibrium. Biological systems. Self-aware systems. Political systems. Social systems. Academic systems. Complex systems. Their elements are typically sub-systems and they are further part of super-systems, so one gets a whole hierarchy of nested systems within systems - that span all of science.

And then you go make models of these systems, find suitable variables, extract relevant parameters to try to understand the system and make predictions. Within the appropriate limits you can neglect the details of the sub-systems and talk about the system and its properties as an 'organized whole'. Might that be neglecting the quark content of molecules in a system called 'cell', or neglecting the hair color of scientists in a system called 'academia'. This procedure of neglecting finer structure and details is widely used, even within physics itself, e.g. if you think about effective theories.

I guess what confused me about this book is the author's proclamation of a paradigm shift and a change towards a "holistic vision", against reductionism, and for abandoning the "mechanistic worldview of the classical disciplines" (he seems to have a problem specifically with physics). Anyway, I think this paradigm shift just passed me by.


PS: Has clarified, thanks to Andreas.

Tuesday, June 17, 2008

Discover Interview with Tegmark

Discover has a nice interview with Max Tegmark

where he talks about all of his four levels of the multiverse. It's quite entertaining to read. I have previously written why I think the mathematical universe hypothesis is nonsense unjustified, to summarize it very briefly: just because we (i.e. human beings) don't know anything except maths without 'human baggage' it doesn't follow from this it is the only thing there can be. Call it The Principle of Finite Imagination: The capacity of the human brain is finite. It is very possible that we simply aren't able to understand 'what' the universe is or why it works how it works. For my general problems with reality, see comments to the Block Universe.

But anyway, despite my disliking of its content, Tegmark's paper is as courageous as entertaining and bestowed this photo series upon you. If I have to read that
Tegmark has pursued this work despite some risk to his career. It took four tries before he could get an early version of the mathematical universe hypothesis published, and when the article finally appeared, an older colleague warned that his “crackpot ideas” could damage his reputation.

and
Q: Right from the start you tried to get this radical idea of yours published. Were you worried about whether it would affect your career?
A: I anticipated problems and did not submit until I had accepted a postdoctoral appointment at Princeton University [...]

it sounds to me like there's something really wrong with the academic system. If young people are afraid of pursuing their interests because it might damage their career this is likely to result in a self-reinforcing deviation of the topics that are investigated from those that are considered interesting. How can you expect science to work under these circumstances?

Sunday, June 15, 2008

PS on Information Overload

As a PS to my yesterday's post on Information Overload, its dangers, and the question whether we might be making a mistake that we won't be able to correct, here is a brilliant article by Nicholas Carr in the recent Atlantic issue

    Is Google Making Us Stupid?
    What the Internet is doing to our brains

    [...]

    Over the past few years I’ve had an uncomfortable sense that someone, or something, has been tinkering with my brain, remapping the neural circuitry, reprogramming the memory. My mind isn’t going—so far as I can tell—but it’s changing. I’m not thinking the way I used to think. I can feel it most strongly when I’m reading. Immersing myself in a book or a lengthy article used to be easy. My mind would get caught up in the narrative or the turns of the argument, and I’d spend hours strolling through long stretches of prose. That’s rarely the case anymore. Now my concentration often starts to drift after two or three pages. I get fidgety, lose the thread, begin looking for something else to do. I feel as if I’m always dragging my wayward brain back to the text. The deep reading that used to come naturally has become a struggle.

If you read one article today, read this one.

Saturday, June 14, 2008

Information Overload

Sorry for having been quiet the last days, I've been busy with too many things and I'm running behind on scheduling some upcoming trips (not to mention preparing the seminars attached to it).

If you have been following this blog for a while, you know that I'm skeptic when it comes to an evaluation of assets and drawbacks of the new online connectivity as to whether it is the assets that weigh more. The bottomline of my posts most often is of the form: Change happens somehow, we'll have to figure out whether it's a change for better and if not, readjust it. (If you memorize this sentence, you'll pretty much get the essence of everything I write). The big question is whether there can be change that hinders its own readjustment which in my post Cast Away I referred to as the 'Fiesta-Feature' - the problem you cause when putting the keys in the trunk that will lock on close.

One of the problems I have been writing about is Information Overload:


“[I]nformation overload is not only caused by the sheer volume of information, but also because of the complexity or confusing structure of information that might overtax the user’s cognitive skill to focus on relevant information ... Therefore Helmersen et al. (p. 2) characterize information overload as “difficulties in locating, retrieving, processing, storing and/or reretrieving information due to the volume of available information.” Information overload may lead to stress, health problems, frustration, disillusionment, depression, as well as impaired judgment and bad decision making ... From an ethical perspective, these consequences of information overload are problematic, because they undermine several basic principles, especially the requirement of participants’ autonomy/self-determination and the nonmaleficence principle.”
Behr, Nosper, Klimmt & Hartmann (2005) Some Practical Considerations of Ethical Issues in Virtual Reality Research, Presence Teleoperators & Virtual Environments 14:6, 668 (2005).

In my post The Spirits That We Called we've been discussing some secondary problems caused by the fact that information people indeed process isn't just what is available, but what is cheaply available. Faced with an overabundance of information, this potential input has to be filtered somehow, and ideally so without much effort - this is what eventually determines what is most likely to be read by many people. This cheapness is becoming more and more important, esp. for our political systems, and is unfortunately a factor that can easily be influenced with money and power. So much about democracy.

Either way, another question that I've raised in the post Can Technology Make us happy? is the conflict of short-term pleasures with long-term happiness. This is pretty much a problem of addiction (though not necessarily in the clinical sense), may that be to TV, online games, constant email checking, or blogging. The question is whether and how such developments will be corrected.

Especially when it comes to email, this is by now a fairly well documented one, as you can see e.g. from the quote about information overflow above, and companies are starting to draw conclusions from that. Among others, Loblaw, U.S. Cellular Corp (via Daily Commercial News) and Intel introduced the E-mail free Friday (via USA Today). Also the Departments of the Canadian government have urged their employees to turn off BlackBerries over night.

The Globe and Mail recently wrote in an article titled No e-mails, please. I'm trying to work
"But now there's a growing awareness that these technological tools can distract us from our work, filling our days with interruptions that, while work-related, prevent us from thinking carefully for any unbroken stretch of time.

That's one reason why companies such as Loblaw, Intel Corp. and U.S. Cellular Corp. are enforcing e-mail-free days, or restricting BlackBerry use in the office.

Others set aside time for creative thinking: Google Inc.'s 20-per-cent rule allows engineers to spend one day a week working on ideas that aren't in their job description. Gmail and Google News both grew out of ideas conceived during 20-per-cent time."


The reason why self-correction works in this case has, unsurprisingly, a priori nothing to do with happiness but with profit. Constantly checking email can be a productivity killer, which is why a small but growing number of companies are trying to do something about it.

It is in this regard very interesting that I read today in the NYT
Lost in E-Mail, Tech Firms Face Self-Made Beast

[...]

Some of the biggest technology firms, including Microsoft, Intel, Google and I.B.M., are banding together to fight information overload. Last week they formed a nonprofit group to study the problem, publicize it and devise ways to help workers — theirs and others — cope with the digital deluge.

[...]

The fractured attention comes at a cost. In the United States, more than $650 billion a year in productivity is lost because of unnecessary interruptions, predominately mundane matters, according to Basex. The firm says that a big chunk of that cost comes from the time it takes people to recover from an interruption and get back to work.

Companies are also realizing that there is money to be made in helping people reduce their digital gluttony. Major corporations around the world are searching for ways to keep software tools from becoming distractions, said John Tang, a researcher at I.B.M., who is a member of the new group."


For me, the big question is though how long will it take for academic non-profit organizations to realize the processing capacity of the human brain is finite. Unfortunately, instant email reply and reliance on being read is a peer-enforced group problem that is very unlikely going to be solved on the individual level.


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Friday, June 13, 2008

The Matter of Everything



    "THE DOCUMENTARY ABOUT NO ORDINARY MATTER

    The Matter Of Everything is a feature documentary that challenges us to see beyond our everyday sense of experience into the unseen universe. From the quantum to the cosmos, The Matter Of Everything journeys deep out of the foundations of nature to reveal what we are, at billionths of the human scale. At that level, physicists at Fermilab, one of the largest particle research facilities in the world, describe a universe that is more unified than ever imagined."


    Website: www.thematterofeverything.com

Wednesday, June 11, 2008

Do you qualify to be German?

I just read in Spiegel Online that from September on anyone who wants to become a German citizen will have to pass a citizenship test with questions to test applicants' knowledge of the country's history, politics and society.

From 33 question the applicants have to answer 17 correctly. Spiegel has a sample citizen test with 7 questions.

To my own surprise, I answered all of them correctly at first attempt without Googling, even the capital of whats-the-name! My sozi-teacher would have been delighted.

Tuesday, June 10, 2008

Bad Hair Day

Summer has finally come to Ontario. Humidity is 100%, people swim on the streets and spend as much time as possible shock-frozen next to the air-conditioning that's as abundant here as it seems to be everywhere in North America. Speaking of conditioning. I have that kind of hair that resists to be put in any form whatsoever and likes to stand off into all directions. I swear it doesn't properly couple to gravity. If a shampoo says 'more volume' I drop it like a hot potato. MORE volume is about the last thing I need.

Humidity reliably turns my hair into a collection of corkscrews. Following a fleeting interest in screwability, here's what the internet told me. Beware, I'm not a chemist:

Hair is made up of 90% keratin, a protein which also makes up skin and nails. Keratin consists of amino acids which link together to form chains called polypeptides. These chains are in turn cross-linked with each other by side bonds of three types: Hydrogen bonds (H), Salt bonds (S), and Disulfide bonds (D) that keep the hair in its shape.


[Figure from this site]


The D-bond and S-bonds are quite strong and keep the hair in the natural form that it likes to grow on your head. If these bonds are broken, the hair can be reshaped, after which the bonds will hold it in the new form. The breaking can be achieved with various chemicals, after which the hair can be brought into a shape that suits you better, and will keep it. That's what e.g. a perm does.

The hydrogen bonds are very easily to break with water. If you make hair wet, and the water dries, the bonds get set up and the hair will stay in the new form. Humid air also causes these bonds to weaken. One result of this is that the hair increases in length. This is why a hair can be used as a hygrometer. Another result of high humidity is that the hair will resist to stay in the form you've tried to bring it in. If you have hair that has the sulfur bonds set for curliness, which is apparently the case for the stuff growing on my head, then the hair will tend to get curlier when the hydrogen bonds relax.

I hope I got that straight ;-)

And here's how that looks like

Monday, June 09, 2008

This and That

Saturday, June 07, 2008

Maps of Science

Interesting website visualizing scienctific research fields based on a co-citiation analysis of journals.




Unfortunately, one can't zoom into the fields, that would be really cool.

I came across the site via this paper
    Mapping the backbone of science
    By Kevin Boyackm Richard Klavans and Katy Boerner
    Scientometrics, Vol. 64, No. 3 (2005) 351.374

which is quite visionary in its aims. Here is a quote from their conclusions:

"The disciplinary map presented here is designed to support decision-making, e.g., the allocation of resources among/between disciplines. However, it also promotes the understanding and teaching of the general structure of science. Although it is a static map, and thus does not reveal how disciplines are born, evolve, or die, it is the broadest static map of science published to date, and thus constitutes another step forward in the study of the structure and evolution of science by scientific means.

Ultimately, maps of science could be based on a much broader set of data (such as scholarly journals, proceedings, patents, grants, and funding opportunities). Alternative units of analysis (clusters of journals, papers, authors, funding sources and/or text) could be generated to address different user needs. Instead of being static, dynamic maps could be generated that show high activity, scientific frontiers, and merging/splitting of scientific areas.

We believe that these global maps of science will enable researchers and practitioners to search for and benefit from results and expertise across scientific boundaries, counterbalancing the increasing fragmentation of science and the resulting duplication of work. These maps of science could also serve as a common data reference system for scholars from all disciplines - analogous to how geologists use the earth itself to index and retrieve data, documents, and expertise, or to how astronomers use astronomical coordinates. If such a reference system were to exist, all researchers could have a bird's eye view of the landscape of science, and could use this landscape to navigate to areas of interest, to communicate results, and to announce discoveries.

This global view - as opposed to doing keyword based searches on the Web or in digital libraries with very little information about the coverage of the queried database or the quality of the result - would give many more people access to scientific results. This, in turn, would lead to more informed citizens and a faster spread of results and practices benefiting all of humanity."

Friday, June 06, 2008

BioFuel

In March, Biofuel was the title story of the Time magazine. In The Clean Energy Scam, Michael Grunwald reports on 'new studies' that investigate closely especially the efficiency in using cropland for growing such 'renewable' energy sources. I was puzzled about the following discussion in which it was 'revealed' that ethanol production from corn does not make sense, neither economically nor ecologically. Instead, under quite general circumstances, more energy is needed to produce the ethanol than is obtained from it.

If one takes into account all energy inputs more than 140% more energy (mostly high value oil and natural gas) is needed to produce a gallon of corn ethanol than is in the ethanol itself. There are various environmental impacts of corn ethanol, including severe soil erosion of valuable cropland, and heavy use of nitrogen fertilizer and pesticides that pollute rivers. Because significant amounts of fossil fuel energy are used in ethanol production, large quantities of carbon dioxide are produced and released into the atmosphere, and during the fermentation process about 25% of the carbon from the sugars and starches is released as carbon dioxide [1]. Besides this, growing the crops takes large amounts of water which in some parts of the US is already becoming an issue that will likely worsen in the soon future.

And that doesn't even touch on the ethical problems it causes because ground that's used for biofuel crops is ground that's not available for food production. (The type of corn used in biofuels is not the same that is used to feed humans.) Some of the richest countries, among them the United States, Brazil, Canada and several European Union states, have large and expanding food-for-fuel industries. The poorer countries, among them Egypt and Venezuela, have been highly critical of biofuels because the crops used to make them take food off the table.

I was puzzled by this biofuel discussion because it wasn't news to me. Okay, I couldn't have quoted the exact numbers or details, but I knew the general sentiment. Neither did I have the impression this was news to commenters on my blog when it was casually mentioned in a previous post. I am not usually following these things too closely, I mean, I have a job and spend most of my time reading papers anyway. So, I think it must have been my younger brother, who is a mechanical engineer, explaining me that, which leaves me wondering how widely known these facts were.

To state the most important fact again and really clearly: Growing 'biofuel' does not make your country more independent of oil and gas resources, because you need more of these resources to grow it than you eventually gain. The only thing it does is a psychologically interesting 'greenization' of energy. You could as well use an oil-powered turbine to pump water up a hill, then let it run down again and call that clean energy from water-power. The energy you gain back is of course less than you invested, but since it's now an 'alternative' energy it deserves governmental subsidies. (I think they've actually been doing that somewhere in Switzerland, but can't recall the details, anybody has a reference?) It's not an investment that makes sense in any way.

I probably would have forgotten about the biofuel, hadn't I read some time later that the German ministry for environment wakes up when hearing biofuel might drive up food prices and utters confused statements ("muss auf den Prüfstand"), before calming down and proclaiming one would hold onto what the plan says. Meanwhile Sean from Cosmic Variance states that Energy Doesn't Grow on Trees and is pleased that "People seem to be gradually catching on to the fact that biofuels are an especially wasteful and dirty energy storage system." Talking to my friends, they confirm my sense that little of that was surprising.

So I tried to find out how 'new' actually is that news. Here's the story. Since the early eighties, there have been dozens of studies showing that ethanol production from corn and other crops is not an economically and ecologically sensible option. It is expensive and under quite general circumstances takes more energy than one gains from it. Two articles by the U.S. Department of Energy (USDOE) dealing with ethanol production using corn for liquid fuels from biomass reported a negative energy return [2,3]. These reports were reviewed by 26 expert U.S. scientists independent of the USDOE; their findings concluded that the conversion of corn into ethanol energy was negative and these findings were unanimously approved. Since then other investigations have confirmed these earlier findings.

In 2002 and 2004 there were reports from the US Department of Agriculture [4,5] in which it was claimed biofuels could have a net energy return (34% in 2002, 67% in 2004). These studies however were based on wrong assumptions that neglected needed energy sources, and the conclusions not appropriate. This has has been documented in further research articles. For an excellent review, see [1].

Now this makes me wonder how can it be possible that this knowledge has been so consequently disregarded? Sure, there's big money in the game, there's lots of people trying to make profit, but how can we life with a system in which scientific studies are just ignored? And now that the problems are catching up with us, and we're possibly seeing the first signs of a global food crisis, I read
"Food-summit draft rejects biofuels control

The final declaration of United Nations food summit will not call for controls on biofuels even though almost every delegate at conference agrees that turning crops into fuel has had some role in raising food prices to crisis point. A draft declaration making the rounds at the UN's Food and Agriculture Organization (FAO), the sponsor of the three-day summit which ends Thursday night, calls only for more study on the effect of biofuels on food security. "

More study?

Why this bothers me: The world economy is a very powerful system that has without any doubt done an incredibly well job increasing wealth, improving the infrastructure and the lives of billions of people. But not in all cases does this pursuit of micro-interests lead to a desirable outcome on the macro-level, especially not when long time and/or distance scales are involved. To put it bluntly: what do I care what happens in a decade somewhere in Africa? Its for this reason that we have political systems that ought to implement these aspects. Unfortunately, our political systems are far too slow and inefficient for this task, especially on a global level.



[1] Pimentel D, Patzek T (2005) Ethanol Production using corn, switchgrass, and wood and biodiesel production using soybean and sunflower. Natural Resources and Research 14(1): 65-76.
[2] ERAB (1980) Gasohol. Energy Research Advisory Board, U.S. Department of Energy, Washington, DC.
[3] ERAB (1981) Biomass Energy. Energy Research Advisory Board, U.S. Department of Energy, Washington, DC.
[4] Shapouri H, Duffield JA, Wang M (2002) The Energy Balance of Corn Ethanol: An Update. USDA, Office of Energy Policy and New Uses, Agricultural Economics. Report No. 813. 14 p.
[5] Shapouri H, Duffield J, McAloon A, Wang M (2004) The 2001 Net Energy Balance of Corn-Ethanol (Preliminary). US Department of Agriculture, Washington, DC.

Thursday, June 05, 2008

Learning to Be Thoughtless

Social norms are unwritten laws. Did you ever go into a grocery store and took somebody else's full cart? Went into a restaurant and ate with your fingers? Went straight to the head of the queue? Went to work wrapped into nothing but a towel? Probably not. And very likely, you haven't spend very much time thinking about it either.

That the effort people make thinking about social norms is less the better established these norms are, is the result of this quite amusing and interesting article


(If you don't have access to the journal, try this draft, which is pretty much similar to the journal version, except that the figures are better.)

It uses a particularly simple model in which `individuals' are represented by simple agents sitting on a circle who chose what to do in a situation (A or B, eat with the fingers or use the fork, wear a towel or a dress). They have a certain search-radius r, that is the number of steps around them in which they observe what the others do. To chose a behavior, in each time-step they do the following: Check out what the neighbors are up to within the search radius, and figure out what the majority does. Then increase search radius to r+1. If the result changes, increase search radius by another step and so on, until it either covers all others or the result does no longer change. Otherwise, if increasing the search radius doesn't result in a change, try decreasing it by one step. If that yields the same result, update search radius to the lower value and figure out whether further decreasing is possible. Adjust behavior to that of the majority within search radius.

It is further assumed that there is some kind of randomness in the system, in that occasionally somebody will just feel like ignoring what the social norm is.

The result of running this model isn't so surprising: If a social norm is already well established, the search radius will decrease into a state where everybody just `knows' what to do. If the system is perturbed by some random shock everybody tries to find out what to do now, and after a while things will settle down in a possibly different, but equally `thoughtless' state.

So, here's a social norm I never understood. Why are letters of recommendation confidential? So confidential, not even the person who the letter is about gets to see them? Having read several letters about myself, I can certify it doesn't kill you. Having read piles of letters about others I still fail to see what the secrecy is good for. The only explanation I can come up with is it's a social norm. As far as I am concerned, it's bad enough there's so much sociology involved in academic hires, somewhat more transparency would certainly be beneficial.

Anyway, what do we learn from this? Question the norms every now and then. It keeps your society mentally flexible and avoids its settling into a thoughtless state.



Related: On the Emergence of Lies

Wednesday, June 04, 2008

PASCOS 2008

This week, the Perimeter Institute hosts the conference PASCOS 08, the the 14th in a series of interdisciplinary symposia on the interface of particle physics, string theory and cosmology.

You can check out the schedule here. Like myself, most of you probably cannot just be in Waterloo, ON, right now - but thanks to the PIRSA service, we can follow all the plenary talks online, and even subscribe to a RSS feed.

I especially liked (conceding a strong personal bias...) this morning's talks by Bill Zajc on the Quark Gluon Plasma at RHIC (and in QCD and String Theory) and by Krishna Rajagopal on the Quark Gluon Plasma in QCD, at RHIC, and in String Theory.

Enjoy.

Monday, June 02, 2008

Scientist's Playground

Hey, I uploaded a video! The memory card of my digicam is full, so I downloaded what's collected on it upon which I found some movie clips I took during my recent visit in Germany. Stefan and I, we more or less stumbled across an interactive exhibition called Science on Tour, which I guess was designed with the purpose to convince children to study physics (and/or to make their parents regret they didn't).

Unfortunately, on their websites the English translations are missing, so apologies. Here are the experiments that I recognized

Especially nice were the equal time curves, but they are not on the video.