Nothingness

The recent issue of Discover magazine has an article by by Tim Folger

Nothingness of Space Could Illuminate the Theory of Everything
Could the vacuum contain dark energy, gravity particles, and frictionless gears?

It is nicely written, scientifically accurate though vague, and its narrative is absolutely pointless - it just ends somewhere and I kept looking for the next page.

The article adds more evidence that headlines are in most cases nonsensical and have rarely something to do with the content of the article. I've been told repeatedly headlines are picked by the editors not the writers, and I find this increasingly annoying. The article by Folger talks a bit about Casimir energy and dark energy. Then it features the idea of 'extracting' energy from the vacuum which could destroy the universe in a chain reaction in which our vacuum reverts to an energetically more favorable state: “If some clever engineer were ever to extract energy from the vacuum, it could set off a chain reaction that would spread at the speed of light and destroy the universe.” At least that wasn't the headline. Finally there are some paragraphs about the LHC and the Higgs and a rather unmotivated mentioning of extra dimensions and M-theory. How the vacuum is supposed to “illuminate” the Theory of Everything remains remarkably unclear throughout the whole article.

John Baez is quoted in various places and is a voice of reason, esp. with regard to the destruction of the universe. About the possibility that the LHC might find the Higgs and only the Higgs, he says

“Well, it would be exciting, but only in the same sense as if you lose your keys and then you find them again. Someone would certainly win a Nobel Prize for it, but after the initial excitement, particle physicists would become grumpy because it would just mean that what we thought was true is true, and all the things we don’t understand we still don’t understand, and there is still no new evidence.”

Sean Carroll is quoted with “we really have to think deeply about what our theories are.”

Amen.

This and That

In the absence of quality blogging time here's some unordered bits of information:

• A group of researchers around Philip Humphrey and David Buote from the University of Irvine in California have determined the mass of a supermassive black hole from the peak temperature of its gas emissions, as a press release from UC Irvine reported on Wednesday. The results obtained with their method match quite well with the results obtained by studying the motion of surrounding visible matter. You find their paper that was just accepted for publication in the Astrophysical Journal on the arxiv at 0801.3461 [astro-ph] "Weighing the Quiescent Central Black Hole in an Elliptical Galaxy with X-ray Emitting Gas"



• Most sentimental story of the week: Olive Riley, allegedly the world's oldest blogger, died at age 108 in Australia. As the Globe and Mail reports, her great-grandson Darren Stone said she loved being able to stay in touch with correspondents all over the world and said she believed it kept her mind active. “It was mind-blowing to her,” Mr. Stone said. “She had people communicating with her from as far away as Russia and America on a continual basis, not just once in a while.” I find this just a lovely example for the global village.



• Most absurd story of the week: Man in New York finds knife in a Subway sandwich. Enjoy.



• Curiosity didn't kill the cat: Cat got accidentally sent over several hundred miles in a package. When it was opened, that cat was alive and well and got re-entangled with her happy owner in Bavaria.



• Completely forgot to mention: I am going Sci-Foo-ing next month! The invitation was a pleasant surprise, I am really excited about it. A certain senior PI faculty member reported that allegedly last year he was the youngest physicist at this unconference, so I guess I'm supposed to bring the average physicists age down. I have like a dozen topics that I'd be interested in discussing and can't quite make up my mind. I hope California stops burning by then.



• Backreaction proudly reports: I wrote a paper! 0807.2838 [gr-qc] "A Bi-Metric Theory with Exchange Symmetry".

Interna

We have good news! As you might recall, after finishing his PhD Stefan started a position as editor for Springer - the scientific publisher with the little horsehead: "Springer" is the German word for "Knight". (The same scientific publisher whose books show up annoyingly often in Google searches without providing as much as a free abstract.)

Anyway, after two years Stefan's contract recently became permanent! ("entfristet" nennt sich das in Neuhochdeutsch).

At the same time, the bureau in Darmstadt where he was located has been moving to Heidelberg (where I recently gave a seminar at the ITP). Commuting from Frankfurt to Heidelberg has turned out to be quite painful, so we have been looking for a new apartment during the last weeks. Meanwhile, we found a very nice place in the Heidelberg area and are now packing boxes, have to decide what to do with the furniture, and I am trying to convince my beloved husband to throw out some cubic meters of clothes and books and paper printouts he'll never use again in his lifetime.

You might be relieved to hear that the availability of a high speed internet connection was a major criterion for picking the new apartment. We are told it will be set up already next week.

The German Academy of Sciences

The UK has its Royal Society, France the Institut de France with its Académie des sciences, Italy has the Accademia Nazionale dei Lincei, and the US the The National Academies with the National Academy of Sciences, which bring together committees of experts in all areas of scientific and technological endeavor [...] to address critical national issues and give advice to the federal government and the public.

So far, Germany has been missing a comparable institution to produce evidence-based statements as a basis for discussions and political decisions. But since today, The German Academy of Sciences Leopoldina is Germany's first National Academy of Sciences - it was officially appointed so in a ceremony with Germany’s Federal President Horst Köhler, who also took over the patronage of the Leopoldina as the National Academy.

The Leopoldina was founded in January 1652 by four physicians in the Free Imperial City of Schweinfurt to explore Nature to the Benefit of the Human Being, and is named after Emperor Leopold I (1640–1705), who was well-known for his interest in the arts and sciences of his time.

Let's hope that the new Academy will establish a fruitful two-way exchange between the inhabitants of the Ivory Tower and the public, or its elected representatives, respectively.

We have only ourselves to judge on each other

Last week, I was talking to a string theorist. We were talking about black holes at the LHC, but I am admittedly presently somewhat tired of the topic. So, since I will be on the market again this fall, I asked how the job situation presently looks like for string theorists. Not good, he said. Having gotten used to the always optimistic US spirit, this came as a surprise to me. People are losing interest, he said, there hasn't been enough progress. He is now looking into loop quantum gravity & Co.

Gee, I thought. Peter is right. There is change knocking on the front door. Should we let it in?

I am watching these developments with interest, but also with some concern. As a continuation of my earlier post on the Marketplace of Ideas, I want to elaborate somewhat on what the differences are between scientific research and the market in economy.

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The Economic System

With regard to our economy, the free market has proved to be an enormously
useful tool, as long as its freedom is guaranteed by appropriate institutions. It works so efficiently because the mechanism that optimizes distribution of goods and money is strikingly simple. It is the individual who chooses where to invest and whether an investment is worth the money or not, which then provides feedback to those producing a good or offering a service. One has in this case a large group of potential buyers that judge on offers by accepting them or not accepting them. This leads the goods to obtain some value, a price that develops out of the interplay of supply and demand.

Buyers don't always act rational and/or are not well informed, so there is some error to this process. People eg might not want to spend arbitrarily much time comparing offers, or they are influenced by fashion trends. Decision science is a fairly recent interdisciplinary field that investigates how people make decisions under which circumstances. Still, it remains the fact that the marketplace works quite well. (Though some of it quirks are less than pleasant - eg a large part of the sudden increase in oil price is due to speculation). However, one important factor influencing people's decisions are advertisements which can substantially skew situations (and are thus subject to regulations).

If we are selling products on the marketplace we have sellers, we have buyers, and as long as the system is set up properly this should lead to an optimal investment of time, money and resources - and eventually free capital for further progress. One could say that a product will tend towards some natural value that optimally balances supply and demand.

This procedure of operation for profit has been so efficient and globally lead to so much progress that it is of little surprise some countries preach it like a religion - an 'invisible hand' guiding us towards wealth and happiness. Ideally, the mechanism of the free market converts our individual 'micro-interests' in 'macro-interests' that are to the benefit of everybody. (A lot can be said about the circumstances under which this works or doesn't work, but this is not the aim of this post.)

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The Academic System

Systems with individuals who pursue interests, and develop strategies that lead to specific dynamics and trends can be found in many situations. The blogosphere is an example. Here we have the bloggers who are trying to increase the number of visitors, comments, and in-links. One of the results are multiple echos of topics that attract interest. Strategies that are useful are being fast, being brief, and being provocative. I leave it to you to decide whether the outcome is desirable.

The academic system is also constituted of individuals who pursue their own interests, and the result should be that the single researcher's strategies ideally lead to progress. As in all other cases this requires however that the system is set up appropriately and the developing individual strategies indeed lead to a desired trend.

For this, one has to be aware of several crucial differences between the academic system and the marketplace of goods:

• First, I dare to say that within academia the relevant factor that scientists aim for is not money but attention, primarily - though not entirely - attention of peers. Those who want to become rich wouldn't stay within academia to begin with. It is however the case today that financial support is closely linked to attention.



• Second, the most important assumption behind there being something like a 'Marketplace of Ideas' is that an idea has a natural value that can be identified in some simple way. It is here where the analogy fails dramatically. If a company produces a candy bar people will like it or don't like it, you will find out very fast. In scientific research, the value of an idea (or a research program) is eventually whether it leads to progress. Progress might not necessarily be an application but simply growth of knowledge and understanding. Developing and judging on the value of an idea is a complicated and time-consuming process, and the judgement itself is in fact one of the main tasks of scientists. It can however take decades until a research program is fully developed and until it is possible to figure out whether an idea is of high value. In academia, people still discuss today things that have been written hundreds of years ago.
  
  The timescale it takes to figure out the value of an idea can depend very much on the field and also on the project. Theoretical physics specifically is a field that is very abstract and working out an idea takes at least 5-10 years. It can take decades for it to be tested.



• Third, between proposing an idea and there being an external indicator as to its value, there is no way to judge on the promise of a research direction other than peer review. And this is the most important difference between our economy and scientific research: Judging on the value of a research program requires an education in the field and expert's knowledge. Scientists are thus buyers and sellers likewise. They provide supply and cause demand. Until an idea is developed sufficiently and can be experimentally tested, we have only ourselves to judge on each other.

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The Fall of the Ivory Tower

Especially because of the third point above, the academic system is extremely fragile and prone to be substantially distorted when under external pressure that influences researchers interests. It is for this reason that traditionally the ivory tower was meant to protect scientists. The ivory tower is now a word used quite cynically to describe the detached academic who doesn't know what people do in real life. But the intention of this detachment was to make scientists independent of financial, political, and social influence. This independence is crucial, and it is not easy to obtain. Rational and objective judgement is essential to science and is simple neither on the personal nor on the community level. The only way that researchers micro-interests can be as objective and well-informed as possible, and that these interests can lead to a desired outcome is to ensure researchers are able to follow their judgement on ideas, unaffected by what fashion, funding and the media says.

This however is presently not the case. There are most prominently three important factors that influence researchers

• Financial pressure: Nothing works without money and typically researchers are funded to work on certain projects, either through grants or because they are hired into specific groups. Projects are funded if they are considered interesting, often based on previous success. Tenure depends on grants obtained. The possibility to hire people depends on grants. The reputation of the place depends on the people and thus on the grants. Now we have a situation where people go where money goes, and money goes where people go, and interest goes where money and people goes - attracting more money and people. A perfect setting to produce bubbles of nothing, based on people telling each other and funding agencies how great their research program is (also called: positive feedback). Money is an extraordinarily powerful tool to direct interests and one has to be extremely careful with using it.



• Peer pressure: Scientists strive for attention and appreciation of peers, which opens the doors to social problems that one has to be aware of and that potentially need to be counteracted by providing incentives, or ensuring appropriate management. Especially in cases when sub-fields specialize there is the trend to misjudge shortcomings of the own research fields, and to neglect criticism by out-group members (this is a well documented phenomenon in sociology). Also, scientists might hesitate to work on topics that potentially could damage their reputation, might prefer topics their peers consider interesting thereby creating fashion trends, and there is the risk that a lot of time is invested in improving social connections which goes on the expenses of time invested in research itself.



• Public attention: Scientists are part of the society they live in and are influenced by what is discussed in the public. It is also not surprising that researchers like to work on topics that cause attention and are appreciated by the public, which is not necessarily a bad thing. However, this delegates quite some influence to the mass media and journalists. In a recent post I mentioned survey results according to which 46% of all scientists consider media contacts to be beneficial to their career. It is a small step from this for researchers to decide working on topics that are of interest for the media is beneficial for their career.

The above mentioned points lead scientists to develop strategies that improve the possibility of surviving within the academic system. The results of such strategies are especially pronounced if competitive pressure is high and the selection works very fast, which in turn creates a system populated by scientists that did well under the present circumstances and thus see no reason to change it. In areas where paying attention to such matters simply is not necessary because sufficient positions exists, these influences might be small or negligible.

Unfortunately, especially theoretical physics presently suffers from a large competitive pressure that leads people to pay attention to these factors. I am very afraid this significantly affects our ability to judge on each other because we are investing too much time in worrying for our career, and because following our own interests might be in conflict with what is strategically a wise decision. Time pressure and lacking future options produce a tendency to dismiss or just ignore new approaches. This is not a problem that originates in funding agencies who in my impression seem to be well aware of the need of 'transformative research' - it is a problem that originates among the researchers who are afraid of wasting time or money in approaches that will not produce presentable outcome for several years. The 5-10 years in which a research program needs unsolicited support to be fully developed is often not available.

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Some suggestions

Some suggestions follow directly from the above:

• Don't tie researchers to topics, but let them chose freely. Scientists should be hired and promoted based only on their ability and creativity, period. No other factors should play any role, and then let them do what they want. This holds true also for younger researchers. Cooperation with senior researchers happens naturally because it is beneficial for both sides, but should not be enforced.



• Support researchers for an appropriate time period. In research the weight shifts strongly towards short term positions. From 1973 to 2005 the share of postdoc positions in academic research in the USA grew from 13% to 27% (numbers: NSF). People who are on short term contracts and under pressure to produce outcome (papers/patents) will hesitate to start projects that do not fit within that timeframe. This totally stalls any progress on topics that take longer to be worked out. Have some faith. If a researcher has done well, just fund him and let him do what he wants. In some fields of science (like theoretical physics), writing a proposal that plans ahead several years and then needing to stick to it is in many cases a procedure that is nonsensical and constrains scientists freedom.



• Don't fall for shortcuts. Under time pressure, people tend to look for easy criteria to judge on other people or their projects. Such might be the citation index, the number of papers, prominent coauthors or grants obtained. In all instances scientists should judge on other's work by themselves. This requires that scientists have enough time for this judgement. Time is essential, but too short in today's research atmosphere. For a thought on how to cut back on researcher's duties, see previous post on Research and Teaching.



• Counteract specialization: In the present system it is almost impossible for a researcher to change fields without risking severe drawbacks for his/her career. One of the reason is that researchers are hired into specific tasks, and for these nobody would be hired who hasn't previously worked on the field. Another problem is that grants typically require having former publications in a field to document expertise. It has been realized already decades ago that progress very often comes from interdisciplinary exchange. It is quite ironic that lots of funding goes into such new inter-disciplines while the possibility for researchers to just change between fields (or even sub-fields!) is hindered. Solution again: Have faith in people who have proved to do good research and just let them follow their interest.



• Reward internal communication and criticism: Science lives from criticism and dialogue. Unfortunately, presently there are about no incentives for researchers to invest time into obtaining and communicating an overview on their or other's research fields. It is basically a waste of time since the thing to do to obtain a position is to make oneselves an expert in some niche where one is the only person. Give credits to people and/or institutions who fulfil this task and create an atmosphere in which the relevance of criticism is acknowledged and its importance appreciated.



• Don't reward advertisement: Advertisement of the own product, in this case an idea or research program, is a tactic widely used to sell goods. The aim is simply to influence buyers. Such a procedure is completely inappropriate for scientific ideas that have to be critically assessed, in papers as well as in proposals. Nobody should be punished for openly presenting and discussing drawbacks of the own research program, eg because he or she might appear not enthusiastic or optimistic enough. Neither talks nor papers should overhype promises or forget to mention problems, because these are 'well known'. The latter also causes a significant problem when it comes to communication with science journalists.

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No Panaceas

I recently had an interesting exchange with Garrett Lisi, who said:

"It's just that the [academic] system seems locked in a poor state right now, so it seems easy to think of steps to make it better."

I am afraid that the more people realize the present system doesn't work well, the more likely they will think it's easy to improve it and fall for panaceas - cheap solutions offering miracle cures. However, putting emphasis on other easy criteria than the previously used ones is not going to solve the problem, it just moves the problem elsewhere. There are no panaceas.

Consider we'd put an emphasis on the 'independent' researcher who works on an 'alternative' approach, who has plenty of single-authored papers and doesn't like mainstream topics. Consider we'd set up the system to preferably reward this type of person. What would we create then if we leave the selective pressure behind the system? People who strive to fulfill these new criteria. To me it seems pretty obvious that this only cures the symptoms, not the disease: One can also have too many 'independent' people, too much emphasis on 'alternative', and cooperation is as far as I am concerned a beneficial trait. The same is the case for over-emphasizing predictions or phenomenology. Just look at the arxiv and see what the outcome is. Money goes into phenomenology. People go where money goes. More money goes where people go. Interest goes where people and money goes. In two decades from now, somebody will come and say: Hey, there is trouble in physics. They are working on all of these cheap little pheno-models, how is ever something supposed to come out of this?

Therefore, the suggestions I had above are aimed at ensuring the system can self-optimize its outcome, by lowering disturbing influence that deviates researcher's work from their actual interest.

On the long run, the only way I see to ensure progress is to scientifically investigate the situation and incorporate asap offered solutions.

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Bottomline

If change knocks on the front door, ask what it wants.

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Post-Scriptum

Re-reading what I wrote, I was just reminded of a paragraph from Lee's 1st book

“All there is of Nature is what is around us. All there is of Being is relations among real, sensible things. All we have of natural law is a world that has made itself. All we may expect of human law is what we can negotiate among ourselves, and what we take as our responsibility. All we may gain of knowledge must be drawn from what we can see with our own eyes and what others tell us they have seen with their eyes. All we may expect of justice is compassion. All we may look up to as judges are each other. All that is possible of utopia is what we make with our own hands. Pray let it be enough.”

~Lee Smolin, The Life of the Cosmos (Epilogue)

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Meta

My FQXi proposal to investigate some of the aspects I discussed here was declined, main reason that it seems to "overlap with studies of the sociology of science, which is a well-developed field, but one in which the principal investigator appears to have no direct professional experience or training". That is entirely correct. I am just a physicist who has had too much time thinking how the academic system sucks, wondering why nobody in it seems to listen to what the sociologists say, and why said sociologists don't come up with practical advices (interdisciplinary research, anybody?). To those of you waiting, this also means there will be no financial support for grad students to participate in our upcoming conference. I am genuinely sorry about this.

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This post is part IV of our series on Science and Democracy. See also: Part I, Part II, Part III.

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TAGS: ACADEMIA, MARKETPLACE OF IDEAS, SCIENCE AND SOCIETY

Scientists and the Mass Media

The recent issue of Science has an article about

Interactions with the Mass Media
Science 11 July 2008, Vol. 321. no. 5886, pp. 204 - 205

which summarizes the result of a survey of 1354 researchers in the United States, Japan, Germany, United Kingdom, and France. The results show that media contacts of scientists in these top R&D countries are more frequent and smooth than was previously thought.

In all five countries, the biggest part of scientists who had contact with the media in the past 3 years rated the impact of those contacts on their careers positively: 46% of the respondents perceived a “mostly positive” impact, whereas only 3% found the impact to be “mostly negative”. Overall, 46% of the respondents perceived a “mostly positive” impact of their interaction with journalists. 57% of the respondents said they were “mostly pleased” about their “latest appearance in the media,” and only 6% were “mostly dissatisfied”.

I find it interesting but also slightly worrisome that such a large fraction of scientists considers media contacts to be beneficial for their career. It would be good to know whether the perceived benefits are actual benefits.

German Citizenship Test

As previously mentioned, Germany has introduced a citizen test for immigrants. Spiegel Online now has the full version with 33 questions:

TAKE THE CITIZENSHIP TEST
Are You Smart Enough to Be German?

I got 32 right, I failed on the colors in the state flag of North Rhine-Westphalia. Outcome:

"Well done! You would have no problem getting a German passport."

I'm relieved to hear. Particularly nice the question:

Which of the following do Germans traditionally do at Easter?



• Leave pumpkins in front of the door
• Decorate a fir tree
• Paint eggs
• Let off fireworks

Hint: if you follow this blog, you know the answer.

They left out however some of the really important questions, here are my suggestions:

1. Besides being a citizen of Frankfurt, what is a 'Frankfurter'



• A: A bakery
• B: A sausage
• C: A flat tire
• D: A drink mixed of beer and lemonade

2. If a German says he will meet you at three-quarter eight (dreiviertel Acht), what does he mean?



• A: 8:45
• B: 8:15
• C: 7:45
• D: Any time between three quarter to and after eight, ie 7:15 - 8:45

3. What did the crowd chant on Nov. 9th '89 at the Brandenburg Gate?



• A: Lasst uns rein - Let us in
• B: Lasst uns raus - Let us out
• C: Wir sind der Staat - We are the state
• D: Wir sind das Volk - We are the people

4. If a Bavarian tells you to "Grüss Gott" - "Say hello to God", he means



• A: Thank you
• B: Hello
• C: Piss off
• D: I died and went to heaven

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(Answers: 1 - B, 2 - I don't know!, 3 - D, 4 - B)

Yes, he can have a dream

But a dream it will likely remain. German newspapers have been discussing back and forth during the last days whether Barack Obama while on visit in Germany should be allowed to speak in front of the Brandenburg Gate at July 24th in Berlin (SPEECH AT BRANDENBURG GATE? -German Politicians Are in an Obama Tizzy). The Berlin mayor Klaus Wowereit says yes, the chancellor Angela Merkel says no. Today the topic made it into the NYT which titles

Prospect of Obama at Brandenburg Gate Divides German Politicians

You didn't ask for my opinion, but in this case I'm with Merkel though she's in the wrong party (can you imagine I'd vote for a party that has a C for Christian in its name?). Obama isn't an elected representative of any nation, at least not yet. It is pretty clear he wants to speak in front of a historically loaden location like the Brandenburg Gate to help the campaign in his own country, and I think Germany should try to stay out of other countries election campaign.

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Aside: I do presently neither receive nor can I send any emails. The problem seems to have occurred about 12 hours ago and before somebody gets up on the east coast it probably won't be resolved. So please don't expect me to reply to any emails I didn't get. In case it's really urgent recall an invention named 'the phone'.

Update 4pm: Email works again.

Research and Teaching

A main topics in today's issue of the Frankfurter Rundschau (one of the major German newspapers) is dedicated to the quality of teaching at universities. Page 3 features an interview with Thomas Metschke who founded the page www.meinprof.de where students can rate their prof's teaching skills (it's all in German I'm afraid.)

Maybe I was particularly unlucky with my lecturers, but the classes I had to take were in the best case useless, in the worst case demotivating, if not debilitating. The quality considerably improved in the cases a prof was spending other people's travel grants to go in vacation and his class was held by one of his students instead. I do well learning from books, so to me it wasn't a huge problem, but still one had to appear and sit through all these hours while somebody was mumbling to the blackboard or got confused about his own notes.

Either way, ever since then I've been wondering why people are forced to teach who apparently have neither the skill nor any desire to, while people who would like to teach first place have a hard time getting a professorship. The idea that those who teach about research should be researchers themselves has a long history in Germany, and I think this is a necessary requirement. But do they have to be active in research while teaching? In practice it seems to me that teaching is often seen as a timeconsuming duty while research is the 'real' thing - it is what brings the colleagues' appreciation, possibly invitations to cool places or journalist's requests. On the other hand, people whose interest clearly is in teaching, and who have experience in research but possibly are not in the top-group have a hard time making it onto a position were they would teach.

Does that make any sense? It raises for me the following two questions

A) Why aren't there more pure research positions at universities? Face it, there are people in the academic system who can be great researchers but are a complete failure with students. There is the kind of people who are complete hermits or just totally nerdy, and who efficiently radiate an aura of get-out-of-my-office. Nothing of which necessarily makes them bad researchers, but where is the place for them?

B) Would it be possible to diversify research jobs by additional training in possibly different secondary disciplines like e.g. in teaching, public outreach, or group management? These are all skills besides the research activities that today are expected of researchers to acquire them just somehow. The advantage of that would be that it could be better documented, tasks could be assigned better, and if you were hiring somebody you'd know better what you are at.

In fact I think this is where the trend will be going. Researchers today are expected to be all-rounders, to do everything with less and less time, under increasingly high pressure. It just doesn't work well. Universities and institutes, as well as private companies, offer an increasing amount of training seminars to improve such secondary skills. I think this is a natural development into a division of labor that the academic system will have to incorporate at some point in order to stay functional.

Recreating the Big Bang?

With the start of the Large Hadron Collider coming closer, the topic is present in the media more than ever. A commonly used motivation is the alleged recreation of the Big Bang (see illustration to the right).

Peter Woit recently mentioned that Martinus Veltman, winner of the '99 Nobelprize in physics, “described claims that the LHC will 'recreate the Big Bang' as 'idiotic', and as 'crap'. He said that this is 'not science', but 'blather', and that the field would come to regret this, arguing that if you start selling the LHC with pseudo-science, you will end up paying for it.”

I am totally with Veltman. But what is behind the story? What does the LHC have to do with the Big Bang?

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The Making Of

It is interesting to trace back how this inaccurate description developed. In February 2000, BBC News wrote on CERN's SPS:

'Little Bang' creates cosmic soup
10 February, 2000

Scientists have created what they describe as a "Little Bang" inside which are the conditions that existed a thousandth of a second after the birth of the Universe in the so-called Big Bang.

Two years later, CNN.com writes about RHIC:

'Little' Big Bang stumps scientists
November 20, 2002

Smashing together atoms to produce conditions similar to those in the first cosmic moments, scientists came up with some startling results that could force them to reexamine their understanding of the universe.

Five more years later we can read on MSNBC about the LHC:

Teams toil underground to re-create big bang
March 2, 2007

It is a $4 billion instrument that scientists at the European Center of Nuclear Research, or CERN, hope to use to re-create the big bang — believed to be the event that caused the beginning of the universe — by crashing protons together at high speed.

Within 7 years we have thus moved from a 'little bang' via a 'little Big Bang' to a complete recreation of the Big Bang, a story which catches on. The TimesOnline writes “The machine, the Large Hadron Collider (LHC), aims to recreate the conditions of the Big Bang, when the universe is thought to have exploded into existence about 14 billion years ago.”, the German magazine Stern titles "Large Hadron Collider" - Urknall im Labor (Big Bang in the Lab), and for the Telegraph the LHC turned into a “Big Bang Machine” that “could destroy the planet” [1].

True, the LHC speeds up particles to higher energies than SPS, but still this is far off from anything similar to the Big Bang.

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The Big Bang

The Big Bang is believed to be the first moment of the universe. Technically seen, it takes place at arbitrarily high energy density. It is commonly expected however that in this regime quantum gravity becomes important, and the density is neither infinitely high nor is the volume arbitrarily small. But still the temperatures for this to happen would be somewhere in the Planckian regime, that is at average energies of about 10¹⁶ TeV.

To our best current understanding, the universe then undergoes a rapid phase of expansion during which all energy densities drop and all matter cools. With dropping temperature, we pass the scale above which we expect Grand Unification and the three forces of the standard model separate. This is believed to be somewhere at 10¹³ TeV. Then around a TeV there is the electroweak phase transition. At some hundred MeV, that is about 10^-4TeV, quarks start to form bound states like protons and neutrons. This is commonly called hadronization. It is this transition that we can now hope to study in appropriately designed collider experiments [2].

After hadronization, at temperatures around one MeV (10^-6TeV), atomic nuclei can form - a process that is called 'nucleosynthesis'. Around this temperature also the only weakly interacting neutrinos decouple [3]. At temperatures of the oder eV (10^-12TeV) atoms form and photons decouple. These photons have been traveling freely since this so called `freeze-out'. We can observe them today in the cosmic microwave background with an average temperature of around 3K (10^-3eV) because they have been further redshifted by a factor 1000 since the freeze-out. After freeze-out, structure formation sets in, first stars, galaxies, solar systems and planets form. Some of these planets might carry intelligent life, some might even have a blogosphere.

For a useful illustration of the universe's timeline, see here.

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The Little Bang

There are several important differences between the conditions created at the LHC and the Big Bang.

1. The LHC main program is proton-proton collisions. There is no sensible way in which one could understand the conditions created in these particle collisions as a thermal density distribution. These are scattering experiments. (Though some of the data obtained in these experiments can have thermal characteristics, this does not mean it was indeed similar to the early universe.) The LHC will also have a heavy ion program in which lead nuclei are collided which each other. In these circumstances it is more appropriate to speak of actually creating an intermediate state with a high density and energy density.



2. However, in such heavy ion collisions, the produced state of high density from the two nuclei expands much more rapidly than would be the case in the early universe. Everything is over within the time span needed for light to cross a few diameters of the colliding lead nuclei, or a few 10^-22 seconds. In fact, the expansion is so rapid that it is not even clear from the outset if one can expect any thermalization. In contrast to this, in the early universe the hadronization transition happens after about the first microsecond, and the Hubble expansion is so slow compared to the back and forth of the quarks and gluons that it's granted the early universe is thermal. (Again, though some of the data obtained in heavy ion experiments has thermal characteristics, this does not mean it was indeed similar to the early universe.)



3. Also, in the early universe the expansion of the matter is due to the expansion of space itself. In the laboratory, it is the matter that expands in an to very good approximation flat and static background. Though this might not make a difference for the cooling of the matter, it is conceptually very different.



4. The typical temperature that is created in heavy ion collisions is some hundred MeV. That is about 19 orders of magnitude below the temperature we expect at the Big Bang.

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Bottomline

The LHC is not a Big Bang machine. It is more accurate to say that with the heavy ion program at the LHC we will be able to create conditions closer to that in the early universe than ever before. This sounds more boring, but at least it isn't blatantly wrong. Aside from this, it is more useful to think of the LHC it as the world's largest microscope, that will help us to peer into the structure of elementary matter to a resolution better than ever before.

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[1] For extensive explanation why it is implausible the LHC will cause the end of the world, see: Black Holes at the LHC - The CERN Safety report, Black Holes at the LHC - again, and Black Holes at the LHC - What can happen?
[2] Please note that we are here talking about temperatures. The energy scales usually quoted for the LHC (14 TeV for pp and about 1150 TeV for Pb-Pb) are total center-of-mass energies, not temperatures.
[3] Since neutrinos decouple considerably earlier than photons, measurement of the cosmic neutrino background could allow us to lock back further than the cosmic microwave background.

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TAGS: LARGE HADRON COLLIDER, BIG BANG, SCIENCE AND SOCIETY, PARTICLE PHYSICS

This and That

• It's summer in the city again - last week saw the first really hot days in Frankfurt. One of the many nice things about Frankfurt is that it's easy to escape to the countryside - the meadows and fields at the foot of the Taunus hills for example are a great place for a after-work walk,
  
  
  
  with the city skyline in the background...
  
  
  
  Both photos have actually been taken from the same place, at around the same time. If you look closely, you can see the shadow of one of the towers projected onto another building, a phenomenon one can witness in Frankfurt at sunset around the summer solstice.
  
  My time in Frankfurt is coming to an end soon, and preparations for the move and all the things involved are one of the main reasons for my sparse blogging activity lately.



• The week also saw the record average price for gasoline so far, with €1.60 per litre, or $9.40 per gallon, which makes commuting to Heidelberg quite expensive. I'm quite happy that my old Twingo is content with a bit more than 5 litres per 100 km, or, eh, has a mileage of about 45 miles per gallon.
  
  I've always found the concept of mileage a bit confusing, not just because of the conversion to strange units such as miles and gallons, but also because of the reciprocal involved. Fortunately, there are now online tools to ease the conversion, and even Google does the job.
  
  It seems that the use of "miles per gallon" can mislead when searching for fuel efficiency - that's because the differences of inverse quantities are not very intuitive. You can check this out for yourself with an (a bit silly...) interactive quiz. But I'm still surprised that this deep insight has made it onto the pages of Science.



• Speaking of Science, this week's edition of the magazine is a Special Issue with reports on results from the first MESSENGER flyby at Mercury last January (subscription required, unfortunately). Which reminds me that I owe someone a longer post about the flyby I should publish soon.

Have a nice weekend!

PS to The End of Theory?

" 'If Darwin had had a computer on his desk,' [the ruddy-faced nonlinear economist W. Brian Arthur] exclaims, 'who knows what he could have discovered!' What indeed: Charles Darwin might have discovered a great deal about computers and very little about nature.

~ John Horgan, From Complexity to Perplexity, SciAm June '95

The End Of Theory?

Chris Anderson, the editor in chief of Wired Magazine, wrote last week an article that you find at the Edge proclaiming

The End of Theory:
The Data Deluge Makes the Scientific Method Obsolete

Anderson claims that our progress in storing and analyzing large amounts of data makes the old-fashioned approach to science – hypothesize, model, test – obsolete. His argument is based on the possibility to analyze data statistically with increasing efficiency, for example online behavior: “Who knows why people do what they do? The point is they do it, and we can track and measure it with unprecedented fidelity. With enough data, the numbers speak for themselves.”

This, he seems to believe, makes models entirely unnecessary. He boldly extends his technologically enthusiastic future vision to encompass all of science:

“Consider physics: Newtonian models were crude approximations of the truth (wrong at the atomic level, but still useful). A hundred years ago, statistically based quantum mechanics offered a better picture — but quantum mechanics is yet another model, and as such it, too, is flawed, no doubt a caricature of a more complex underlying reality. The reason physics has drifted into theoretical
speculation about n-dimensional grand unified models over the past few decades (the "beautiful story" phase of a discipline starved of data) is that we don't know how to run the experiments that would falsify the hypotheses — the energies are too high, the accelerators too expensive, and so on.

Now biology is heading in the same direction... ”

Examples he provides rely on statistical analysis of data. It doesn’t seem to occur to him that this isn’t all of science. It strikes me as necessary to actually point out the reason why we develop models is to understand. Fitting a collection of data is part of it, but we construct a model to gain insight and make progress based on what we have learned. The point is to go beyond the range in which we have data.

If you collect petabytes over petabytes about human behavior or genomes and analyze them running ever more sophisticated codes, this is certainly useful. Increasingly better tools can indeed lead to progress in varios areas of science, dominantly in those areas that are struggling with huge amounts of data and that will benefit a lot from pattern recognition and efficient data classification. But will you ever be able to see farther than others standing on the shoulders of a database?

If you had collected a googol of examples for stable hydrogen atoms, would this have lead you to discover quantum mechanics, and all the achievements following from it? If you had collected data describing all the motions of stars and galaxies in minuscule details, would this have lead you to conclude space-time is a four-dimensional continuum? Would you ever have understood gravitational lensing? Would you ever have been able to conclude the universe is expanding from the data you gathered? You could have assembled the whole particle data booklet as a collection of cross-sections measured in experiments, and whatever you do within that range you could predict reasonably well. Bould would this have let you predict the Omega minus, the tau, the higgs?

Anderson concludes

“The new availability of huge amounts of data, along with the statistical tools to crunch these numbers, offers a whole new way of understanding the world. Correlation supersedes causation, and science can advance even without coherent models, unified theories, or really any mechanistic explanation at all.”

With data analysis only, we might be able to discover hidden knowledge. But without models science can not advance beyond the optimal use of available data – without models the frontiers of our knowledge are set by computing power, not by ingenuity. Making the crucial step to identify a basic principle and extend it beyond the current reach is (at least so far) an entirely human enterprise. The requirement that a model be not only coherent but also consistent is a strong guiding principle that has pointed us into the direction of progress during the last centuries. If Anderson’s “kind of thinking is poised to go mainstream,” as he writes, then we might indeed be reaching the end of theory. Yet, this end will have nothing to do with the scientific method becoming obsolete, but with a lack of understanding what science is all about to begin with.

PS: I wrote this while on the train, and now that I am back connected to the weird wild web I see that Sean Carroll wrote a comment earlier with the same flavor, so did Gordon Watts. John Horgan wrote about problem solving without understanding, and plenty of other people I don't know added their opinion. This immediate resonance indeed cheers me up. Maybe, science will have a chance. Leaves me wondering whether writing articles that cross the line of provocation to nonsense is becoming fashionable.

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See also: Models and Theories.

PS to Canada Day

After you could recently test whether you qualify to be German, for Canada Day the Globe and Mail offers a similar questionaire "What's the score, eh?" to see whether you'd make a good Canadian/American. I scored 6/10 for both Canadian and American (mostly guessing though). Have fun!

Happy Canada Day

July 1st is Canada Day. Seems I missed it every time since I live in Canada, much like I've missed every 4th of July while in the USA. Anyway, here is what you are supposed to do: "Canada Day is celebrated with barbeques, parades, music, and of course fireworks in the evening in most of the cities especially in Ottawa with thousands Canadian flags and Canadians singing Oh Canada." Ideally this sounds like this:

If you want to sing along, here's the lyrics, comes of course in English and French.

Besides singing and barbequeing you are apparently supposed to buy lots of stuff in red and white with a maple leaf on it, like flags, hats, towels, pens, keyrings and flip-flops that they sell everywhere from mother's day on. I am pretty sure you can equip your whole household in Oh-Canada-design if you'd try. Anyway, I am in Paris (France, not Paris, Ontario), but happy holidays to our Canadian visitors :-)

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.)

This and That

• Event of the week: Germany made it into the EURO 2008 finals! They will play against Spain on Sunday 2:45 pm ECT.


• Most bizzare news of the week: Banana over Texas doesn't fly


• If the world could vote... we could just make Obama president and save a lot of money on more campaigning.


• Picture of the Week: Sunset over Mars
  
  
  (Click for larger version. Image Credit: NASA/JPL/Texas A&M/Cornell)


• Quotation of the week:

“Out of intense complexities intense simplicities emerge.”

~ Winston Churchill

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.

Seminar in Heidelberg

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

[Click to enlarge]
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).


[Click to enlarge]

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.

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.

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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.

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* 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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TAGS: BLACK HOLE, INFORMATION LOSS, PHYSICS