Short Items

  • On Monday there will be symposia at Stanford featuring the Breakthrough Prize winners, with streaming video available. For the morning program, with dignitaries and such, see here. The Mathematics symposium will run 11-5, the program is here, streaming video here. The Physics symposium is also 11-5, no program yet, but streaming video will be here. If you’re in Berkeley they have an event to watch the videos at International House, see here.
  • Tomorrow in Paris will be the Seminaire Bourbaki, supposedly you can watch the talks online here.
  • Latest news on the Journal of K-theory front (for background, see here) is that the Editorial Board has resigned and is starting up a new journal, to be called Annals of K-theory and published by MSP. The story seems to be that the Journal of K-theory was very profitable, but the profits were going personally to the managing editor, Anthony Bak. Evidently he refused to agree to demands to change this arrangement, so was removed from the K-theory Foundation set up to use funds from the journal, and the other editors (except one) resigned. They are encouraging university libraries to consider canceling subscriptions to the Journal of K-theory, but it’s not clear this is possible, since such subscriptions are now often part of bundles.
  • If you’d like to see what the theory group at CERN is up to, take a look at presentations at their retreat, which ends today.

Update: The program for Monday’s Breakthrough Prize physics symposium is available. It reveals that there will be 3 joint winners of this year’s $3 million. I’m betting Polchinski and two others, most likely Strominger and Vafa. The physics speakers get 15 minutes to give a talk, 5 minutes for questions. Mathematicians get twice as long, a total of 40 minutes/talk.

Update: It looks like mathematicians too are getting in on the Hollywood thing. Next week, sandwiched in between Diane von Furstenberg and Jennifer Lawrence, Terry Tao will appear on the Colbert show.

Update: The Terry Tao Colbert show segment is here.

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Quantum Mechanics and Spacetime in the 21st Century

This evening’s Hollywood-style entertainment came from the Perimeter Institute, where they had a big public event, live-streamed to the world, featuring Nima Arkani-Hamed speaking on Quantum Mechanics and Spacetime in the 21st Century. You should be able to watch the thing soon from the Perimeter site, should be posted at some point here.

The talk was pretty much the same as many other such Arkani-Hamed talks, quite close to the one at the IAS nearly four years ago, discussed here. In this format he can’t go on forever, was cut off by around an hour and a half, so said he couldn’t get to the third part of the talk, which might have been the 21st century part (amplituhedron?). As in the IAS talk, what he did cover was first mostly the 1960s sort of arguments that Weinberg describes in the first volume of his textbook about the constraints on consistent relativistic QFTs. Then an advertisement for the Veneziano model and string theory. The last part of the talk was a long advertisement for SUSY, ending with an acknowledgement that it wasn’t showing up at the LHC. He’s now giving 2018 as the date for when we’ll know about LHC-scale SUSY, which is moved up from the 2020 of the IAS talk of 2011, but still very different than the “year or so after LHC startup” he was saying in 2005. The current plan is for maybe 10 inverse-fb next year, 50 in 2016. If nothing shows up then, I don’t see that the next 50-100 supposedly coming by 2018 have any real chance of finding SUSY.

One thing that struck me about the talk was its odd combination of over-the-top enthusiasm (“this is the greatest time ever!”) and intense defensiveness. He kept emphasizing the claim that theorists, even without experiment to keep them honest, were working with highly constrained rules, that it was very hard to do anything not obviously wrong. He denied sociology had to do with what unsuccessful ideas people decide to pursue. He didn’t address at all the “not even wrong” problem: what about the things like the landscape, baroque constructions that evade being wrong by being empty? I like a lot this picture and quote from Perimeter:

If you manage to find one idea that’s not obviously wrong, it’s a big accomplishment. Now, that’s not to say it’s right. But not obviously being wrong is already a huge accomplishment in this field.

I think the defensiveness here that’s coming through is very personal. He’s gotten a $3 million award and a reputation as a leader of the field for ideas that haven’t worked out, but which he can defend as “not obviously wrong” and thus a “huge accomplishment”.

All in all, the talk was very backward looking, recapitulating the SUSY/string theory ideology that has led us to where we are. It looks like he’s planning on hanging in until 2018 with the same story, only then maybe admitting failure (and possibly going for “the multiverse did it, we never had a chance” cop-out). He did end with an upbeat claim that the SUSY picture being all wrong would be very exciting, opening up the field by showing we need something completely new. The obvious question for him is “you pretty clearly wouldn’t now bet $10 on SUSY at the LHC, so why wait?” Why not stop giving promotional talks about SUSY? One thing he could have done that would have generated some excitement in the field would be to have pitched out the two-thirds of the talk he did give, publicly saying these ideas aren’t working, and talked about something from this century, amplitudes or whatever, the part of the talk he never got to.

Well, maybe in 2018…

You can watch the talk here, along with some online commentary in a chat box that was rolling during the talk.

Update: There was also a more technical talk at Perimeter by Arkani-Hamed, earlier in the day, on Cosmological Collider Physics. The video doesn’t seem to be available yet though.

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Hollywood Theoretical Physics Week

Just got back from an opening night showing of the new sci-fi film Interstellar at the Ziegfeld theater here in New York. If you want some idea of what the film is about, trailers are here and here. Warning: spoilers in next paragraph, skip that if you care.

To me the big plot surprise was that the human race is saved by the theoretical physicist. An elderly theoretical physicist has been trying to solve some equation for gravity his entire career. If he solves it this will somehow save the human race (which has just about ruined its planet). Turns out, he wasn’t being honest, he knew how to solve the equation, but to save the planet, you need to reconcile quantum theory and gravity. Only way to do this is to go into a black hole and get the “quantum data”. Dad (Matthew McConaughey) does this, then manages to transmit the “quantum data” via Morse code to his daughter, a theoretical physicist who has taken over from the old guy, who has died. She uses the “quantum data” to write something on the blackboard that flashes by (maybe a 10d gravitational action), this somehow saves the human race. Before we get to this point, lots of plot involving going through a wormhole (looks kind of like what going through a wormhole always looks like), and various time spent on exotic planets orbiting a black hole.

The black hole portrayal is one that great effort went into on the accuracy front, with Kip Thorne involved. He and the film’s director have a book coming out Friday, The Science of Interstellar, and there’s a TV documentary about the science behind the movie. Evidently this film has been in the works for a while: John Preskill tells the story here of a 2006 meeting with Steven Spielberg to discuss the film, also attended by Andrei Linde, Lisa Randall, Savas Dimopoulos, Mark Wise and Thorne.

Anyway, I enjoyed the film, even though I’m not usually a big fan of sci-fi films.

Opening in a few days is another major Hollywood effort centered around theoretical physics, quantum gravity and black holes: the Hawking biopic, The Theory of Everything. A trailer is here. I’ll probably see that this weekend and will report back.

For yet a third Hollywood-type event opening this week and featuring a theoretical physicist, quantum gravity and black holes, see this trailer. You can watch this Thursday night, more info here.

Finally, it’s not really Hollywood unless you have an awards ceremony featuring Hollywood stars. This Sunday night, some lucky string theorist will get a $3 million check for his work on quantum gravity and black holes. Seth MacFarlane is hosting, more details here. From what I recall, the argument for setting up this huge prize for theoretical physicists was that they don’t get enough public attention…

Update: I hadn’t noticed that there’s another film opening this week featuring theoretical physicists, The Principle, with trailer here. I wrote a bit about this early this year here.

: Phil Plait really doesn’t like the film, finding much of the plot scientifically implausible. Of course he’s right about that, but it makes one wonder if he has seen many sci-fi films. From my limited experience, this one is about average on the implausibility meter.

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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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