Last Week’s Hype

When looking at the nonsense spread around the media by this week’s university press-release-driven hype about string field theory “explaining quantum mechanics”, I realized that maybe I shouldn’t have ignored last week’s university press-release-driven hype, which was about the multiverse “explaining quantum mechanics”. For that one the press release is New quantum theory is out of this parallel world and the paper is here. It has generated all sorts of press stories, with a typical example Parallel Universes Exist – And Could Explain All Physics, Says Griffith University Study.

Sharing the credit or blame for this with the Griffith University press office is the APS and its Physical Review X, which published the paper here. The APS Editor in Chief explains here that

In recent years, however, we have seen a strong need of some researchers to have their best scientific contributions published in highly selective and small journals that can disseminate those contributions broadly and offer them high visibility.

The idea seems to be that if you want “high visibility”, and you’ve got $1700 to pay for it, Physical Review X is there to get you into the media. They seem to have realized though that maybe the “parallel worlds explain quantum mechanics” might be seen as going too far, so have put out an editorial justifying its publication.

Posted in This Week's Hype | 13 Comments

This Week’s Hype

From commenter Hendrik, there’s the news that USC has put out a press release claiming that String Theory Could Be the Foundation of Quantum Mechanics. These claims are based on this paper, which argues that finding the Heisenberg commutation relations in a string field theory calculation means string field theory can be the foundation of quantum mechanics.

In my quantum mechanics course this semester, I’m now up to around chapter 13 or so of the notes available here. Last class I was pointing out that one already sees the Heisenberg commutation relations in classical Hamiltonian mechanics. The functions on phase space are a Lie algebra, satisfying commutation relations given by the Poisson bracket. These relations are determined by knowing what happens on linear functions, together with the Leibniz rule. On linear functions, the commutation relations are Heisenberg’s.

So, I think the discovery out of USC is an even greater one: string field theory can explain not only quantum mechanics, but classical mechanics too.

Update: I should have realized that this thing already had one wave of hype earlier this year, courtesy of Tom Siegfried, which I wrote about here. This new wave comes courtesy of Physics Letters, which thought this worth publishing, and USC, which thought a press release was a good idea.

Posted in Quantum Mechanics, This Week's Hype | 5 Comments

News, Interesting and Otherwise

On the side of interesting good news, I just heard that yet another Fields Medalist has a blog. This time it’s David Mumford, who is blogging here, with his latest posting about path integrals.

His website contains a wealth of other very worthwhile material, including copies of pretty much all of his papers, some of which had been quite hard to find. Much of Mumford’s career has been in the field of algebraic geometry, where he is a towering figure for mathematicians working during the past few decades. This is not just due to his ideas, but also to his expository talents, which have made many of his monographs and papers the standard place young mathematicians have gone to learn parts of the subject.

Michael Schmitt’s Collider Blog is not new, but it’s great to see that after a period of relative quiet he’s been very active there. His postings from the last couple months give some great detailed explanations of recent news from HEP experimental analyses.

The news from Mochizuki is that there will be a workshop in March on his work, with proceedings to be published. Go Yamashita will be giving two weeks of lectures there. One can hope that this is good news, in that it promises the possibility of an exposition of Mochizuki’s claimed proof of the abc conjecture that will allow other mathematicians to finally understand it well enough to evaluate it.

On the much less interesting news front, multiverse mania continues. Much of this mania seems to have to do with people’s fascination with the idea of different copies of themselves doing somewhat different things an infinite number of times elsewhere. I fear that in my case the multiverse is just causing me to do the same thing an infinite number of times in this universe, which is really tedious. In any case, latest developments are:

  • Nathalie Wolchover and Peter Byrne have a new piece at Quanta: In a Multiverse, What Are the Odds?, which leads with the news that “the multiverse camp is growing”, while headlining the obvious “measure” problem that you can’t calculate anything with the idea. Paul Steinhardt is quoted as saying

    The multiverse idea is baroque, unnatural, untestable and, in the end, dangerous to science and society.

    which is about right, but the rest of the article is mostly dubious claims from the multiverse promotion crowd. More to come next week, looks like the usual bubble collision business.

  • Ars Technica has a report on last week’s debate in Brooklyn about the multiverse. Tegmark was on the pro-multiverse side, Wilczek on the anti-side, Janna Levin in the middle. According to the reporter

    Overall, Wilczek seemed to get the better of this part of the debate.

    Much of the debate seemed to be about the “Many Worlds” interpretation, with Wilczek describing this as an empty idea: “metaphysical baggage added on”, and Tegmark rather enthusiastic about this kind of thing. On the cosmological multiverse, I gather Wilczek’s attitude wasn’t so much negative as that it was too speculative to be interesting.

  • What started this multiverse obsession among prominent theorists was the work by KKLT and others supposedly showing that you could get the right cosmological constant in string theory, but that when you did so you ended up with an exponentially large number of possibilities and a likely loss of any predictivity. At the time I thought that was the end of that line of thought in string theory, but instead it turned out to be the beginning of the bizarre period of multiverse mania
    we now live in.
    The latest news is that KKLT doesn’t actually work, that you can’t get stable string vacua that way. I don’t think though that this will have any effect on multiverse mania and its use as an excuse for the failure of string theory unification. It seems to me that we’re now ten years down the road from the point when discussion revolved around actual models and people thought maybe they could calculate something. As far as this stuff goes, we’re now not only at John Horgan’s “End of Science”, but gone past it already and deep into something different.
Posted in Experimental HEP News, Multiverse Mania, Uncategorized | 7 Comments

Breakthrough Prize Ceremony

There’s a story in Variety this afternoon announcing that Seth MacFarlane will be the host this year for the ceremony in Silicon Valley announcing the 2015 Breakthrough Prizes. MacFarlane was the host of the 2013 Oscars. Other celebrities there to award prizes will include Kate Beckinsale, Benedict Cumberbatch, Cameron Diaz, Jon Hamm and Eddie Redmayne. The ceremony will be televised, not live, but November 15 at 6pm on the Discovery Channel.

The announcements that evening will include awards of up to 6 $3 million prizes in the life sciences. The physics prizes this year, funded by Yuri Milner, will include a $3 million prize and one or more $100,000 prizes for young researchers. The past practice of awarding $300,000 to semi-finalists for the $3 million seems to have been stopped, after Joe Polchinski collected a couple of these. Polchinski seems to be the odds-on favorite for the $3 million this year. Another possibility would be Strominger and Vafa, also semi-finalists last year. I suppose there’s an outside chance that the committee making the choice, which is dominated by string theorists, will decide that a non-string theorist is worth recognizing.

The Mathematics prize is funded by Milner and Mark Zuckerberg. The winners there are already known, see here.

The next day there is an announced symposium scheduled to be held at Stanford to honor the prize winners in the life sciences (see here). Last year there was a similar symposium in physics right after the ceremony, so one could guess that such things might be planned for physics and math as well.

Update: There will be separate math and physics symposia on Monday, and an evening lecture from the Physics winner. A little more detail here. The math symposium will be at Stanford, live-streamed to Berkeley, Stanford details and RSVP here.

Posted in Uncategorized | 12 Comments

Yet More News

  • Charlie Munger, the billionaire business associate of Warren Buffett, has donated $65 million to the KITP at UCSB for the construction of a residence for visitors. For more on this, see a UCSB story, a New York Times article, and for some background, 90-year old Munger’s explanation that “I won’t need it where I’m going”.
  • On the other coast, today and tomorrow at Princeton there will be a workshop on string cosmology and inflation. They have a list of questions to be addressed, including

    Are there any plausible alternatives to string/M-theory as a fundamental theory of physics?

    Does string theory make any cosmological predictions? Does it exclude anything?

    As far as I can tell, there’s an odd consensus set of answers to these two questions among string theorists. No, string theory makes no predictions about cosmology, but also no, there are no alternatives.

  • For an interesting discussion of the problems raised by this sort of “no possible predictions, but no alternatives” situation, see this debate involving John Horgan, David Tong and Tara Shears. Horgan does a good job of pointing out the problem. Tong’s defense of string theory relies heavily on claiming that it is highly mathematically rigid, so mathematical consistency is what can give us faith in it. One problem with this is that the whole string theory landscape picture is an extremely ill-defined conjectural framework, the opposite of mathematically rigid. Yes, there are parts of string theory that seem to be mathematically consistent and lead to interesting results. The problem is that those have nothing to do with what is observed about fundamental physics.
  • Jim Gates has an article about Sticking with SUSY, despite no evidence from the LHC. He explains that the thing he finds most convincing about SUSY is the cancellation in divergent vacuum energies between fermions and bosons (or at least that’s how I interpret his comments). I’m actually somewhat in sympathy with this. One thing I’ve been writing about in my quantum mechanics notes is the beautiful parallelism between “bosonic” and “fermionic” quantization. A fundamental theory needs both, and likely has some super-algebra of symmetries acting on it. I just don’t though see a good argument for the realization of this general idea in terms of the standard kinds of extensions of the Poincaré algebra to a superalgebra. These don’t appear to tell us anything about physics we know about, and predict physics we don’t see.
  • I was hoping to have time last Sunday to see a discussion at the French Embassy between John Nash and Cedric Villani, part of their Festival Albertine. Unfortunately I ran out of time to do this, but luckily for you and me, video is available here.
Posted in Uncategorized | 26 Comments

Various News

Various news about the usual topics:

  • Natalie Wolchover at Quanta magazine keeps coming up with great, in-depth stories about interesting new topics in physics that are getting no attention elsewhere. Her latest is about the universality of the Tracy-Widom distribution.
  • The LHC is cooling down, in preparation for a restart early next year. Nature has a good story about what is going on here. Latest status and plans are described here. The current plan is to start beam recommissioning next March, have 1 fb-1 by mid-June, in time to perhaps have some results to report at EPS-HEP2015 at the end of July. Another 10 fb-1 would be accumulated later on, before a heavy-ion run late in the year.

    In the long term, by 2023 there should be 300 fb-1 and many components of the machine and the experiments will start to become unusable due to radiation damage. Planning is going ahead for “Phase-II”, or the HL-LHC, with Bertolucci’s comment that “It is inconceivable under any reasonable scenario to stop the LHC program at that point”.

  • Nature has an editorial this week about What lessons can be learned from the presentation of the gravitational-waves story?, pointing to a planned discussion next week about Lessons in the communication of science from the BICEP2 story. I’ve already written extensively about this, but since the editorial refers to bloggers (and I know some people at Nature were unhappy with my blog entry about this, which was poorly worded), I’ll take another opportunity to do so.

    From the purely scientific point of view, this is a pretty straightforward situation. The BICEP2 people fooled themselves into thinking that they had something much more exciting (primordial gravitational waves + evidence for inflation) than what they really had (a good measurement of B-mode polarization at one frequency). They then wrote a paper with over-optimistic claims, which later blew up in their face. This is perfectly normal science.

    What’s not normal science is the behavior of a lot of theorists in response to the BICEP2 claims. The Stanford University Linde video and its 3 million downloads will live forever as an example of misguided PR for science. The comments from theorists about the significance of this for string theory that Nature quoted were an embarrassment for the field (why not just say that you could get any value of r out of string theory?), and even worse were the publicity campaigns from Linde, Guth and Carroll aiming to convince the public that this was evidence for the multiverse.

    What’s the lesson for science journalists? Take a hard look at the behavior of some prominent theorists in this story, and draw the obvious conclusions for your future coverage of developments in this field of science.

  • Just noticed that Sean Carroll is now trying to raise research funding online with a website devoted to attracting private funding. Will be interesting to see if that works, maybe it will become a model for how to fund this kind of research.
  • One of the few things I’d change about my book written ten years ago would be the discussion of the philosophy of science “demarcation problem”, that of deciding what is science and what isn’t. Only after writing the book did I learn about the distinction between a “progressive” and “degenerating” research program due to Lakatos, which is a very good way of addressing the question of how to evaluate string theory. I also missed a paper that came out a few years ago by Johannson and Matsubara on String theory and general methodology. At one point they write that the string theory landscape business shows that:

    String theory is a degenerative programme, according to Lakatos’ criterion.

    There’s a lot more in the paper, it’s a good example of what I’ve seen too little of, philosophers of science engaging with the real issues here.

  • For the latest on the string landscape, there was a conference last week on Fine-tuning, Anthropics and the String Landscape. See if you can find anything there like a plausible idea for how to get any testable physics, I couldn’t. Alan Guth’s introductory talk mainly explains why the measure problem means you can’t predict anything, but then ends with a claim that physicists take the multiverse seriously anyway, quoting Weinberg from 2005 about Martin Rees’s dog.
    Back in 2004-5, the expectation was that the string theory landscape could be used to predict whether SUSY breaking would take place at a high or low scale (see for instance here). That idea is long dead, and no other proposal for a prediction has replaced it. So, the string landscape is itself a degenerating research program. What do philosophers of science call it when a research program degenerates into something else, and that research program in turn degenerates. A (degenerating)2 research program?
  • The standard defence of string theory these days acknowledges that it can’t explain particle physics, but claims it has had great success in quantum gravity. Next spring the KITP will have a program on quantum gravity foundations. The description of the program has a lot to say about “deep connections between quantum information theory and gravity”, no mention of string theory. There seems to be a move away from string theory and a convergence between the KITP and the sort of alternative research favored by the Perimeter Institute.
  • Speaking next month on Quantum Mechanics and Spacetime in the 21st Century at Perimeter will be Nima Arkani-Hamed, one of the organizers of the KITP program. Not clear what he’ll be arguing for then, but he did just give a talk at an Oxford workshop on New geometric structures in scattering amplitudes, with the title “The Amplituhedron, Scattering Amplitudes, and the Wavefunction of the Universe”. I’m curious to see how he gets the Wavefunction of the Universe, although I suppose one should keep in mind his comments here.
  • Not announced yet what the price of tickets to Arkani-Hamed will be. For a real rock star of physics though, I think you want Brian Cox, who is on tour in Australia. Premium tickets there are about $175 US.

: The latest on the Journal of K-theory situation, from algtop-l

Dear Colleagues,

The time has come to advise your librarians to cancel the subscription to the Journal of K-Theory. The precious money could be better spent elsewhere.

As you know the journal is going through a crisis. The most recent development is that the Bak family has written to Cambridge University Press informing them that they are under a contractual obligation to keep publishing the journal through the end of 2017, whether they like it or not. I haven’t seen the contract in question, not have I seen the letter from the Bak family to Cambridge University Press, hence I cannot comment on the legal merits of the case. The Baks evidently feel confident, Tony Bak has accepted at least one paper for the 2015 edition of the journal without clearing it with any of the other editors.

The Baks might be right, Cambridge University Press might have no choice but to continue publishing the journal. But the vast majority of the editors will be walking out and the scientific standards of the journal are bound to plummet. It would be a waste of money to continue subscribing.

Yours, Amnon

Posted in Uncategorized | 24 Comments

Quick Links

  • This month’s Physics Today has a long article by Wojciech Zurek, Quantum Darwinism, classical reality, and the randomness of quantum jumps. I’m not sure if there’s anything new there, but it’s a very clear exposition of what seems to me the most penetrating point of view on the measurement problem in quantum mechanics, one that gets far too little attention in the press.

    I’d like to know what this makes me in terms of various ideologies of the interpretation of QM. Am I a quantum Darwinist, or maybe a Zurekian?

  • At another extreme, getting lots of media attention while not saying anything substantive, there’s the multiverse of the Many Worlds interpretation. The media campaign to promote this is still in high gear. Recent examples include Brian Cox: ‘Multiverse’ makes sense at BBC News, this week’s New Scientist, which has a bunch of things including Multiverse me: Should I care about my other selves?, and an upcoming program here in New York that tells us that:

    We may live in a multiverse in which every possibility happens and with each new possibility the universe branches off into another of many worlds.

    The New Scientist article has Don Page pointing out that this explains the problem of evil. God likes the idea of everything possible happening all the time so much he’d rather not be bothered to stop bad things from happening:

    “God has values,” he says. “He wants us to enjoy life, but he also wants to create an elegant universe.” To God the importance of elegance comes before that of suffering, which, Page infers, is why bad things happen. “God won’t collapse the wave function to cure people of cancer, or prevent earthquakes or whatever, because that would make the universe much more inelegant.”

    For Page, that is an intellectually satisfying solution to the problem of evil. And what’s more, many worlds may even take care of free will. Page doesn’t actually believe we have free will, because he feels we live in a reality in which God determines everything, so it is impossible for humans to act independently. But in the many-worlds interpretation every possible action is actually taken. “It doesn’t mean that it’s fixed that I do one particular course of action. In the multiverse, I’m doing all of them,” says Page.

  • On the math front, I just noticed that Pieter Belmans has a blog. One of the many nice things there is his “atlas” for Spec Z[x].
  • Over at Persiflage, anyone interested in how NSF grant applications in mathematics are evaluated can find an extensive and well-informed discussion.
  • Videos from last week’s Heidelberg Laureate Forum (which features Fields Medalists and others) are available here.
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Thirtieth Anniversary of the First Superstring Revolution

Today’s about the date that I’d pick for the 30th anniversary of the First Superstring Revolution. Witten’s paper Some Properties of O(32) Superstrings arrived at the journal Physics Letters on September 28,1984, so presumably was finished and sent out around September 25.

The effect of this paper on the field was a bombshell. Witten was at the time far and away the most influential person in the field, regularly producing staggeringly original work that was having a huge impact. The arrival that fall of a preprint from him announcing that he had stopped work on everything else, and now had what looked like a viable, consistent unified theory of everything, one that he claimed was determined by a single parameter and made predictions (“It predicts axions and stable Nielsen-Olesen vortex lines”) was the true First Superstring Revolution.

I wrote about this in some detail ten years ago, for the 20th anniversary, so won’t repeat what is here and here, supplemented by comments from Larry Yaffe. For something more recent along the same lines, see here.

Ten years ago the 20th anniversary of the First Superstring Revolution was celebrated with a symposium at Aspen, but as far as I know, no one has organized a 30th anniversary celebration. There are now many, many known ways of trying to get unification out of strings, with the original 1984 hope that anomaly cancellation gave a more or less unique possibility long gone. As for unification itself, thirty years later Witten remains a true believer in the vision that came to him in September 1984 (see here and here), although he now seems to see little hope for vindication during his lifetime.

Posted in Uncategorized | 33 Comments

Horgan Interview With Witten

Back in 1996 John Horgan’s The End of Science appeared, which included material from a fascinating 1991 interview of Edward Witten. I had mixed feelings when reading this. On the one hand, Horgan was doing something truly remarkable, challenging Witten in a way that no one else dared. This was 7 years after the “First Superstring Revolution”, and it was starting to become clear that string theory was not working out as hoped. No journalist other than Horgan though was talking about this, or willing to confront someone of Witten’s stature with difficult questions. Pretty much every other story in the press stuck to the simple narrative that Witten was a genius, and superstring theory a great success. On the other hand, Horgan did use his author’s freedom to edit and frame the interview to make Witten look bad (today he admits the Witten profile was “pretty snarky”), so he was landing some low blows, against a rather gracious opponent.

This year Witten won the Kyoto Prize, and I was shocked to hear that Horgan was the person chosen to interview him. Witten rarely gives interviews and I would have thought that Horgan would be the last person in the world he’d agree to an interview with, given his past experience. The interview is now available here.

This time around Horgan avoids the snark, and asks some straightforward questions about whether Witten’s views have changed since 1991, and what he now thinks about string theory, the multiverse, anthropics, etc. I have to admit that I find Witten’s answers depressing, in contrast to Witten’s advisor David Gross’s current take on these issues (discussed here). About anthropics, Witten’s “I don’t like it, but may be the way to go” contrasts with Gross’s “cop-out”, and his insistence on string theory as the way forward contrasts to Gross’s emphasis on the fertility of quantum field theory.

Back in 1996, after the appearance of Horgan’s book, Gross and Witten wrote in to the Wall Street Journal (reproduced here) to argue that Horgan was wrong, since string theory would be tested by finding SUSY at the Tevatron, or, failing that, definitely at the LHC. We all know how well that has worked out, and Gross seems to have learned a lesson from this. Witten on the other hand has moved on to even more dubious testability claims (e.g. that the string theory landscape can be tested by “seeing a signature of a prior phase transition in the CMB”). From the 1996 claim that vindication would come “in the next decade”, he now is talking about “200 years from now”. His one point of close agreement with Gross is that both agree that not knowing what string theory is when time-dependent effects are large is a big problem, one that has seen no progress.

By a couple years from now, the idea of making progress in our lifetime by seeing SUSY at the LHC, then going on to use this to learn about string theory should be finally finished off. Already Gross seems to have evolved from the 1991 point of view to a more promising one, perhaps Witten at some point will start to do the same.

: The AMS has something similar, a Mathematical Moment with Witten. Pretty much everything said about string theory is exactly the same as thirty years ago, only change is that the story used to be that string theory would get some vindication at the LHC, now it’s:

The verification of superstring theory is probably a long way off, but could be found here on Earth, using particle accelerators (possibly much more powerful than those of today)

consistent with the “200 years” estimate from the Horgan interview.

Posted in Uncategorized | 27 Comments

Planck: It’s Just Dust

The Planck paper with results on dust in the BICEP2 patch of sky is now out, see here. I’m sure experts will weigh in soon and I’ll link to such discussions, but my non-expert take is that Planck is saying that what BICEP2 saw is likely just dust. See section 6 of the paper, especially figure 9 which appears to show that BICEP2’s claimed value of r=.2 is just what you’d expect from dust.

: More details from Natalie Wolchover and Sean Carroll.

Looks like Scientific American will have to pulp this month’s magazine, with its Lawrence Krauss cover story about how BICEP2 is experimental evidence for quantum gravity and the multiverse.

Update: For more press coverage, see Nature, New Scientist, BBC News, The Guardian, the Washington Post, the Daily Mail and the New York Times.

The best explanation for all this that I’ve seen of course is from a blogger, Sesh Nadathur at Blank on the Map.

Update: Jester has a sensible take on this fiasco here. It now seems that release of the full Planck polarization results has been pushed back from October to “late November”, just before the early December conference planned long ago to discuss the results. The joint analysis of BICEP2/Planck data that will show if there’s any evidence of something besides dust is supposed to be released at the same time.

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