Not Even Wrong

Some wag at the Wall Street Journal put the headline Don’t Buy Into the Supercollider Hype on today’s Op-Ed piece by Michio Kaku about the LHC, which describes its significance as follows:

The LHC might shed light on the “theory of everything,” a single theory which can explain all fundamental forces of the universe, a theory which eluded Albert Einstein for the last 30 years of his life. This is the Holy Grail of physics. Einstein hoped it would allow us to “read the Mind of God.”

Today, the leading (and only) candidate for this fabled theory of everything is called “string theory,” which is what I do for for a living. Our visible universe, according to this theory, represents only the lowest vibration of tiny vibrating strings. The LHC might find something called “sparticles,” or super particles, which represent higher vibrations of the string. If so, the LHC might even verify the existence of higher dimensions of space-time, which would truly be an earth-shaking discovery.

If I were an experimentalist or accelerator scientist working on the LHC, I might have a problem with the fact that the biggest media outlets are having theorists, often string theorists, be the ones to tell the public about the LHC (yesterday was Brian Greene’s turn, in the New York Times). Many such stories imply that the LHC will somehow tell us something about string theory, while even one of the blogosphere’s most enthusiastic string theory supporters puts the probability of this at about half of one-percent.

For some hype-free LHC predictions based on serious science that I fully endorse, see Resonaances, where the probability of seeing anything relevant to string theory isn’t even listed, and supersymmetry is given a one-tenth of one percent chance, on the grounds:

1% is a typical fine-tuning of susy models, and the additional factor of .1 is because it makes me puke.

which seems about right. The probability of the LHC producing black holes is given as something exponentially small, somewhat less than the probability of producing dragons.

This week the Perimeter Institute is hosting an unusual conference on Science in the 21st Century. One of the organizers is Sabine Hossenfelder, who has a posting discussing the conference here, and may have some more about it at her blog later.

Many of the talks are now available on-line here. I’ve only had time to watch a couple of them, but one that I found worth paying attention to was Lee Smolin’s. He covered some of the same issues discussed in his book, including the question of what science is, the ethics of how it is pursued, and the difficulties of encouraging new ideas. The discussion with the audience was also quite fascinating, including an exchange about differences between the American and British academic systems, with a British participant describing his shock at seeing how much the “American academic system is a training in sycophancy”.

The topic of blogs came up mainly in a section where Smolin discussed the ethical importance of scientists putting their name and reputation behind what they have to say about their science. He characterized anonymous criticism as one of the main reasons for the low signal/noise ratio and nasty environment of the comment sections of many blogs, describing this as far worse than anything he had encountered in his professional career, and something that is giving science a bad name. The theoretical physics group at Harvard in the 1970s was given as an example of about the worst it could get in academia. At the end of the discussion session, Paul Ginsparg took him to task about this, saying that he had been there too and it wasn’t that bad. I was there at the same time as both of them, and remember it as a rather unfriendly environment with a quite high arrogance level. But, with faculty like Coleman, Weinberg, Glashow, and postdocs like Witten, the talent and accomplishments of the people involved seemed to justify quite a bit of arrogance.

Ginsparg went on to agree with Smolin about anonymity on blogs, comparing trying to have a serious discussion in such an environment to trying to do so in a Fellini movie, being attacked by dwarves wearing masks.

Update: One talk I highly recommend is that of Eric Weinstein, with the title Sheldon Glashow Owes me a Dollar (and 17 years of interest): What happens in the marketplace of ideas when the endless frontier meets the efficient frontier? Eric’s talk includes a wide variety of thought-provoking and entertaining attempts to bring ideas from economics and finance into thinking about how science gets done and whether it can be done more efficiently.

There’s a media storm about the LHC building up as CERN makes last minute preparations to circulate a first beam in the machine. Cosmic Variance has live-blogging about this by a group of theorists, and Tommaso Dorigo will be in the CMS control room. He just might blog about this. For up-to-the-minute news, try the LHC beam commissioning site. Here’s the plan for tomorrow, and the latest news: they’re ready to get started at 6am tomorrow Geneva time. I’ll be asleep.

Starting tomorrow, daily news reports about progress should appear here. They’ve got a very detailed plan for steps to go through, here’s where they are now, here’s where they hope to be Thursday and Friday.

Roger Highfield has gone out and asked several theorists for LHC predictions, with the following results.

About supersymmetry:

About the Higgs:

(anyone know who took the other side of that bet?)

John March-Russell goes all-out:

…our quest for a source of almost unlimited climate-friendly energy might be answered by the creation of exotic unstable, but long-lived, charged particles… It might also turn out that the number of space and time dimensions is ambiguous…

The first attempt to circulate a beam in the LHC is still set for next Wednesday, and the media is already full of LHC stories, with a lot more to come next week. Events are being organized all over the world to celebrate the day, including a 1:30 am pajama party at Fermilab (see here). Today’s Wall Street Journal carries a page one story about preparations at CERN that focus on improvisational comedy training for physicists to help them communicate.

For more serious news from the LHC, you can try following progress at CERN’s startup site for the public, or at the technical LHC commissioning site. Latest available minutes from the Installation and Commissioning Committee are here, including a timeline and objectives for the next few days and for September 10. The “also going on” column for September 10 lists just “chaos”.

Science magazine has some excellent LHC-related stories in this week’s issue. In this one, various people explain what the LHC is looking for and why it will take a while to get results. Gordy Kane is having none of that though, predicting discovery of supersymmetry next month:

“We predict a signature that they could see with five events,” says Michigan’s Kane. “They could see it in the first week of running in October.”

Another article, Researchers, Place Your Bets!, features bloggers Tommaso Dorigo and Jacques Distler. Tommaso has bet that the LHC will see no deviations from the standard model, although from what I remember, he did this just because if this happens it will be so depressing that at least some cash will cheer him up. Gordy Kane and Stuart Raby claim supersymmetry is such a sure thing that they can’t find anyone who will bet against it. Distler’s comment on this is:

I wonder how hard they tried.

The same article gives links to sites where you can bet on the Higgs boson discovery date.

Nature magazine is running an LHC-related editorial Cool Philosophies in this week’s issue. It is inspired by an interesting recent preprint by philosopher of science Alexei Grinbaum: On the eve of the LHC: conceptual questions in high-energy physics. Grinbaum gives an extensive discussion of the current state of particle theory and its societal context. He ends with a philosophical section on fine-tuning and currently popular anthropic arguments, arguing that these often invoke an invalid use of counterfactuals.

There were some comments about this in a previous posting, but I thought it worth remarking on the unusual situation that papers have started to appear reproducing plots of new data from the PAMELA satellite, even though no such data has been officially released.

This all seems to have started with a July 31 talk at ICHEP 2008, with slides here, but evidently some other slides of preliminary data were flashed on the screen. There was a news story in Nature about this, but still no official release of data. Then, on August 20th there was this talk at idm2008, with no slides made available on-line, but interesting slides again flashed. Evidently some enterprising theorist decided to do some of his or her own data acquisition.

Soon, a preprint on Minimal Dark Matter predictions and the PAMELA positron excess was on the arXiv, complete with PAMELA data, with the notation:

the preliminary data points for positron and antiproton fluxes plotted in our figures have been extracted from a photo of the slides taken during the talk, and can thereby slightly differ from the data that the PAMELA collaboration will officially publish.

There are now at least two other papers on the arXiv featuring PAMELA data, evidently from the same source, here and here. Andrew Jaffe has a new blog posting up entitled Stealing Data? where he expresses discomfort with this situation. I can’t quite see that one is “stealing” data if it is being presented at major conferences.

Are there any of my readers out there who can tell us what’s up with PAMELA?

Update: Nature has a new article about PAMELA being “outed by paparazzi physicists”. One of the paparazzi, Marco Cirelli, is quoted as saying that “we had our digital cameras ready”, and claiming that the PAMELA people at the conference didn’t have a problem with this. On the other hand, a PAMELA PI is quoted as being “very, very upset” about this.

And I should have linked earlier to this posting at Resonaances: Hot Photos of PAMELA.

Update: According to Science News, the problem is not a Nature embargo. They just haven’t finished a paper yet:

“We plan to have final results ready by early October and submit a paper to a peer-reviewed journal,” Boezio told Science News. Until then, he says, the findings remain preliminary, and “We prefer to withhold further comments.”

There’s a conference at Harvard this week celebrating (somewhat early) the 60th birthday of the geometer Shing-Tung Yau. Since I was passing through Cambridge on the way back from a short vacation, I managed to catch a few of the talks, including two quite nice ones on mathematical physics from Is Singer and Edward Witten.

Singer’s talk was entitled “The Interface between Geometry and Physics, 1967-2007”, and summarized some of the advances in this area that he has been involved with over the years. 1967 was the year of a Battelle conference in Seattle on the intersection of mathematics and physics, organized by DeWitt [2/12/21: Chris DeWitt tells me this was Cecile DeWitt-Morette] and Wheeler. Singer displayed a copy of a 1966 letter from Feynman to Wheeler turning down an invitation to attend, with the explanation

I am not interested in what today’s mathematicians find interesting.

At the 1967 conference Robert Geroch talked on the topic of singularities in GR, and Singer recalled inviting Geroch to talk at the 1973 geometry conference at Stanford on this topic and the positive mass conjecture. By 1975 Singer had learned from Jim Simons at Stony Brook that non-abelian gauge fields were exactly the connections on principal G-bundles studied by mathematicians. The news of the BPST instanton solution and its significance for physics caused him to seriously start working in this area, work conducted with Hitchin and Atiyah at Oxford. They made use of the index theorem to both calculate the dimension of the moduli space of instantons, and to show that the Dirac operator had zero-modes in instanton backgrounds. Later, Atiyah and Singer interpreted the local gauge anomaly using the farmilies index theorem.

Just as Atiyah did at his recent talk at the Bott conference, Singer interspersed his historical talk with remarks identifying unsolved problems that he thinks are worth attention. The first of these has to do with K-theory, extended to depend not just on vector bundles, but on vector bundles with connection. Here the open problem has to do with the analog of the families index theorem. There’s a topological index (that takes values in the extended K-theory of the family), and the open problem is to define an appropriate analytical index and show topological=analytical equality. Singer had been hoping to have some new results to report on this, but he says that things turned out to be trickier than he had expected, so maybe he’ll have an answer at Yau’s 65th birthday.

The next topic was that of quantum Yang-Mills theory and the Millennium problem of proving the existence of a mass gap. Singer talked mainly about 2+1 YM, his conversations with Feynman about this, and his hopes that the positivity of the sectional curvature of the natural Riemannian connection on the space of gauge potentials modulo gauge transformations could be exploited to prove that there must be a mass gap. Proving this in 2+1d was his second open problem.

His final topic was mirror symmetry and S-duality. Here he speculated that this (and M-theory in general) might have something to do with a phenomenon from operator algebra theory. Unlike for N by N matrices, where all maximal abelian subalgebras of self-adjoint operators are conjugate, for certain C* algebras (rings of operators of type II), there are inequivalent such maximal abelian subalgebras. I gather that his idea is that these might correspond to the existence of lots of inequivalent limits of M-theory.

The next morning Witten gave a talk on quantum Yang-Mills and the Millennium problem, saying that this was in response to a request from Yau to explain at a basic level to a wide mathematical audience what this is about. He gave an extremely lucid explanation of the mass gap problem, taking the Hamiltonian point of view. This supplements what he and Jaffe did in the official write-up of the problem, which deals more with the Euclidean picture. As motivation, he explained in detail what happens in the Abelian case, where one can compute everything and there is no mass gap. The audience was appreciative and I think got something out of this, unlike quite a few talks of physicists to mathematicians, which tend to start at much too high a level of complexity, ensuring that only experts can follow.

Witten avoided one aspect of this problem, the one that most fascinates me, that of how you handle the gauge symmetry. In the Abelian case there are several equivalent ways of doing this, but in the non-Abelian case, at least in the continuum, one needs to understand BRST symmetry non-perturbatively, and this remains a difficult problem, one with deep connections to open problems in mathematics.

David Gross just finished giving the closing talk at Strings 2008, on the outlook for string theory, following a talk by Hirosi Ooguri summarizing the conference. Strings 2009 will be in Rome next June, and it appears that there is a tentative plan to have Strings 2010 in College Station, Texas.

Gross began his talk by recalling his days as a postdoc at CERN in the late 60s, working on an early version of string theory (e.g. trying to extend the Veneziano model). At the time he felt CERN was a great center of theory, but somewhat of an experimental backwater, with the real action he was interested in happening at SLAC. Now, forty years later both string theory and CERN have flourished. CERN is in the process of becoming the single world umbrella lab doing particle physics, driving all the others out of business. Unfortunately, Gross sees the same thing happening in particle theory and seems rather pleased about it, saying that only one umbrella in theoretical physics will survive, string theory, eating up everything else. Except LQG, which he says has not yet been brought under the umbrella, and “we’re not sure we want to”.

I found this display of string theory triumphalism truly appalling. The fact of the matter is that string theory has failed miserably to do what it was supposed to do, explain unexplained features of the standard model and predict what happens beyond it. Under the circumstances, to claim victory and write out of particle theory anything that doesn’t fit under the string theory “umbrella” is completely inappropriate. The message to any young particle theorist from Gross was clear: fall in line with string theory ideology, or there will be no place for you under the “umbrella”, i.e. no job for you (the phenomenologists have their own umbrella, you better try that one). The fact that HEP experiment is being forced to consolidate in one lab by economic realities is a really unfortunate one. There is no similar reason for HEP theory to be forced to consolidate around one topic.

Later on in the talk, Gross started channeling Lee Smolin and me, urging young people to stop sticking to the same well-worn ideas, to stop looking under the same lampposts, and to go out and search for something really new. He argued that they would find wandering in the darkness less competitive since few people were doing it. It was unclear whether one is allowed to get out from under the umbrella when one goes out to investigate the darkness, presumably not.

While he made lots of positive comments about current work in string theory in order to rally the troops, much of his talk was rather pessimistic and critical of trends in string theory research. He acknowledged that there hadn’t been any “great breakthroughs” in the field in quite a while. String phenomenology was described an attempt to make string theory “a predictive, or at least imitative” framework. He didn’t comment on what it means for theorists to give up on predicting nature, and settling for imitating it.

About the LHC, he acknowledged that it is unlikely to have anything to say about string theory. He finds the idea of seeing black holes, strings, etc. “extremely unlikely”, but is betting that the Higgs and supersymmetry will show up. Unfortunately, even if supersymmetry is found “it’s not clear that we’re going to learn enough”, this won’t answer any deep questions about string theory or prove that it is relevant. His “most optimistic hope” is that the LHC will see something unexpected, and “we will realize that this was an obvious prediction of string theory”. He notes that this is “almost our last chance”, if nothing relevant to string theory shows up at this energy scale, it is unlikely that anything relevant will show up at any energy scale accessible for an extremely long time.

Gross commented on two topics that hadn’t been mentioned in the talks. He’s still hoping for a non-anthropic explanation of the CC, and noted that no speaker had brought up the anthropic landscape explanation of the CC, with it getting a mention only at one after-dinner talk. Despite what Susskind claims, perhaps the battle between the anthropicists and their opponents is not going so well for the anthopic side. They may get pushed out from underneath the umbrella…

The second topic was the still unsolved question of “what is string theory?”. Gross noted that there were no talks on string field theory, since it and most other ideas about how to define string theory non-perturbatively have gone nowhere. The one thing that is still alive is AdS/CFT, which now completely dominates the subject. More and more, particle theory research under the umbrella is focused only on things related to the duality of N=4 SSYM and string theory on AdS⁵ x S⁵. Gross noted the progress toward showing this duality, with the planar limit perhaps being done within the next few years.

By the way, in Ooguri’s talk, he mentions an AdS/CFT discrepancy that has been resolved, saying he was surprised that some blogger didn’t claim this discrepancy as disproof of AdS/CFT. Lubos in his commentary helpfully explains that Ooguri was referring to “numerous pigs and Woits”. Since I’ve never argued that there’s a problem with AdS/CFT duality, I guess he must be talking about someone else. Maybe Jacques Distler has some postings about problems with AdS/CFT that I missed.

Gross takes the attitude that there is no more value in working on “tests” of AdS/CFT, that the conjecture is now well-tested and it is time to move on to try and understand what AdS/CFT is good for, especially what it says about the question of “what string theory is?”. The planar limit is just the classical limit, and he discusses prospects for moving beyond it [and beyond AdS/CFT, to other backgrounds]. On the QFT side, this means deforming the gauge theory by non-renormalizable operators, so it is not clear what to do.

Update: More summary commentary and prizes at Resonaances. Clifford Johnson watched Gross’s talk and summarizes it as follows:

David Gross summed it all up, took stock of where we are, and where we aren’t, and looked forward. A sort of “state of the union” speech if you like. And the state is good. Very good indeed.