David E. Kaplan interview

There’s a long interview with David E. Kaplan (not the same person as David B. Kaplan…) by David Zierler at the AIP Oral Histories site. The whole thing is quite interesting and I recommend reading it, but I do want to point out that it shows that I’m a voice of moderation on the string theory issue. Some extracts follow:

About Ann Nelson and string theory in the 1990s:

She was extremely dismissive of string theory, and thought it was—you know, there was—my impression from her and from other people of that generation that weren’t doing string theory was that the string theorists were colluding in a sense, or were dismissing anything but string theory, and deciding that if you did string theory then you’re much smarter than the people who are not doing string theory. There was some unhappiness in the theoretical field. And the cancellation of the SSC probably added to that tension between the two.

But I don’t think she came of it from taking a side. I think she looked at the situation and said, “String theory is total bullshit.” In the mid-’80s, there were some realizations—there were some consistency checks that kind of worked in string theory, and people got super excited. Oh, my god, string—yeah, it could be the, you know, underlying thing to particle physics. But that was it.

The successes after that were few and far between. But there was an obsessive—like we’re studying the theory of quantum gravity. And it was deridingly called the theory of everything. And then they took that on, you know. We’re studying the theory of everything. And then the young people who want to do the greatest stuff would go to string theory. And there was a concern and some upset by the people not doing string theory that they’re absorbing a lot of people to do this crap, which is not very physics like. “It’s I believe the theory, and so I’m going to study all aspects of it, and maybe one day we’ll connect it with the physical world.” As opposed to I believe in the phenomenon, and I’m trying to explain that and more, and so I’m going to try out different theories and see what they’re consequences are.

And now I look back, and it’s obvious that string theory was bullshit in the sense of there were so many people working on it, and they were not manifesting any real progress externally. It was all internal consistency checks and things like that. And so at the time, you know, whenever it came up—and it didn’t come up much because there were no string theorists in Seattle—she was just very dismissive, like, you know, “What are those people doing? I don’t know what they’re doing.” [laugh]

About being a postdoc at SLAC:

There were a lot of string theorists at Stanford. I didn’t understand any of those talks. Or sometimes when the talks were not in strings, Lenny Susskind would yell at the speaker that this is bullshit or whatever, da, da, da, da—you know, abusive at some level. So Stanford was weird in that way.

About realizing what was going on in string theory, his evaluation of past (Strominger-Vafa) and current claims about string theory and black holes:

But—so I don’t—and it’s part of probably why I didn’t understand—I didn’t think of myself as a physicist because there’s a lot of physicists working very hard on what? I don’t know what they’re working on. It’s not—you know, I used to just think I’m too stupid to understand what they’re working on. And finally reading some of those papers, they’re not what—it’s stupid. There’s a lot of stupid stuff in there. String theory really is just stupid. It’s unbelievably stupid. There’s so many people who are working on it that don’t actually know physics that they can’t even describe a physical characteristic of the thing they’re calculating. They’re missing the whole thing.

So that’s when I realized string theory is like a video game. There are people just addicted to it. That’s all that’s happening. And it’s couched in the theory of everything and da, da, da, da.

So that’s all. I just kind of—I learned quite a bit about these things. And then I saw the people like Lenny Susskind, who was terrorizing people who work on regular physics, as just a plain asshole. That there are actual people who are deciding string theory’s important, wanting to do string theory, and they’re even protecting the field. And some of those people are talking about how entropy now of a black hole can be described as a geometric thing, an entanglement, and that Hawking’s paradox about evaporating black holes is really wormholes, virtual wormholes coming from the inside to the outside, and all kinds of language. And you could test information theory of black holes using atomic physics experiments. And it’s literally bullshit.

There are people—prominent people—in physics who say, “I’m applying for this money from the DOE, but I know it’s bullshit.” And then there are experimental atomic physicists who don’t know and are shocked to learn that “What? String theorists don’t have a Hamiltonian? They don’t actually have a [laugh] description? What am I testing?”

So I have converted a little bit to the opinions of my predecessors, only because I’ve actually done the work. I’ve actually tried to understand black holes of late, and I’ve gone back to those papers which are the breakthrough, celebrated, amazing papers about black holes, and there’s nothing in them. It’s really—it’s just a very simplistic picture where, look, if you take this hyper-simplistic picture, these numbers match these numbers, which means thinking about a black hole having entropy is correct, da, da, da, da, da.

No matter that the black hole they’re talking about is extremal. It doesn’t actually Hawking radiate. It’s a totally hyper-supersymmetric, multiple charges, free parameters. So now that I’ve finally dug into it, I realize that—not that all humanities fields are bad. But it’s much more like a humanities field where there are the prominent people in the field, and they decide what’s interesting. And that if you impress those people, you can get ahead. But that dictates then what research is done. And they’re not going to discover anything in that context. They’re not going to get anywhere. There’s not a lot of people doing—you know—thinking outside the box or just thinking diff…you know, doing different things, you know.

About the argument that string theory must be worthwhile because lots of people are doing it:

Zierler:

What is your response to a string theorist who would say, and I know this because one has said this to me, “Look, four people were doing this in 1968, 20 people were doing it in 1984, 1,000 people were doing it in 2000, and now there’s 6,000 people who are doing string theory all over the world. And that’s proof that there’s something here that’s worthwhile”? What is your response to that line of reasoning?

Kaplan:

[laugh] Take those numbers, continue the exponential, and apply it to Christianity—

Zierler:

[laugh]

Kaplan:

—and Islam and Judaism and Buddhism. Give me a fucking break. They’re describing a religion that can attract and addict people. That is exactly the kind of statement that shows it’s bullshit and non-scientific. They’ve proven it for me that they are not about discovering something. They’re about dominating the field for the purpose of what? That’s proof? Give me a break. Give me a fucking break. Slavery was very popular, and became widely used. Nazism. Come on. You can take extreme examples and show that that is so non-scientific and sick that the progress they have made is to get more people to work on something that isn’t producing anything. Oh, man, I wish you didn’t tell me that. [laugh]

About the current state of the field:

There are so many things to think about. I don’t know what narrowed our field. I don’t see it as we’re dying because we’re coming to the limits of what we can do, the limits of what we can calculate in string theory, and the limits of how big of a ring we can build. I think most people are just doing useless stuff.

And so that’s why I—the whole depression or whatever, that’s a product of the non-willingness to feel stupid by the majority of our field. Expertise is more important to them than discovery. And that’s what I think is happening. And so what we’re seeing is not the death of the field, but the death of a direction that is being committed to by 98% of them.

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37 Responses to David E. Kaplan interview

  1. Anonyrat says:

    Via the Kaplan interview, an antidote to string theory that you might enjoy:
    https://arxiv.org/pdf/2204.03085.pdf

  2. Marco says:

    String Theory is the field in which it is possible to publish several papers every year and thus believe that you are a theoretical physicist like Einstein or Dirac. I did my PhD in string theory and then dropped out of physics out of disappointment. In addition, the community of physicists, at least here in Spain, is very self-centered and hierarchical. If you are a student, you cannot criticize, you have to obey. Your professors, who have been working on string theory for years, give you as the only argument to pay attention to them that they have been working on string theory for years and their experience is beyond the doubts of a 25-year-old about string theory. So you have to shut up, and if you want to have a PhD you have to eat String Theory. I finally dropped out of physics, disappointed not only by the so-called theory of everything, but above all by the aggressive attitude of my professors. Too much ego is a sign that deep down they know they’re wrong, but… “I’ve been working on this for many years, so it has to be true.”

  3. Alessandro Strumia says:

    You would enjoy the video of the 2001 CERN Christmas recital. Despite being done at the peak of string popularity, it featured physicists reading the sacred Schwarz-Witten Green book dressed as barbosi Talibans chanting “why are we doing this? why are we doing this?”. When I joined the recital, CERN offered me one of the two available positions: either string theorist or dog. That’s why I bark in the video. Hopefully it has now been cancelled because it contains the politically-incorrect word Christmas.

  4. Peter Woit says:

    Mitchell Porter,
    Kaplan explains that his attitude towards string theory used to be less hostile, that at some recent point he came to the conclusion that the late 90s analysis that it is “bullshit” was correct. Perhaps Nelson later did or would have come to the same conclusion.

    A strange aspect of the interview is that it does not cover at all Kaplan’s film “Particle Fever” (made 10 years ago, see https://www.math.columbia.edu/~woit/wordpress/?p=6308) in which he and Arkani-Hamed are filmed going on uncritically about LHC implications for multiverse scenarios made popular by string theorists.

    An important aspect of this story (and for understanding at any time what is going on in theory) is that of battles over funding. By the mid-90s string theorists were winning the battle with phenomenologists for funding and positions (for some data, see https://particle.physics.ucdavis.edu/rumor/doku.php?id=statistics), which had a lot to do with Nelson and others feelings about string theory. By 2005 things were starting to change, partly due to the “large extra dimensions” models of people like Arkani-Hamed and Randall which brought together the string and phenomenology people. If you were a phenomenologist you could add something about this and string theory to your grant proposal and benefit from the string theory hype yourself. The upcoming LHC and the the increasing problems of string theory also helped a lot starting around this period.

    I haven’t really been paying attention to current trends in how funding affects what people are working on, but for string theorists being able to claim that they are working on “quantum information” surely is helpful on the grant front.

  5. Brathmore says:

    Peter – I would be interested in your assessment of the following claims made by one of the physicists that your post references:

    https://www.preposterousuniverse.com/blog/2005/07/21/two-cheers-for-string-theory/#comment-228

    1. “That said, the field and its practitioners have redeemed themselves by discovering deeper and more interesting insights into Quantum Field Theory then ever would have been found by phenomenologists or by traditional formal quantum field theorists.”

    2. “Spin-offs of string theory including D-branes, AdS/CFT, orbifolds, dualities, supersymmetry, and new dimensions have all found their way into testable particle physics phenomenological model building, and particle theory would be would be completely moribund without them.”

    3. “Also some interesting experiments have been done in response to some of the string-inspired models, such as tests of the gravitational inverse square law at the sub-centimeter level, that would not otherwise have been conceived, and which very well might find something revolutionary. Other approaches to quantum gravity dont offer many such spin-offs, as far as I can tell, and neither do other formal approaches to quantum field theory.”

    4. “Finally, as to whether string theory and its predictive power should be thought of in an analogous way as quantum field theory—ADS/CFT has taught us that string theory IS quantum field theory and vice versa. For instance QCD, which is certainly a quantum field theory, can very likely also be formulated as a string theory and the ADS/QCD approach shows that the latter formulation can give interesting insights into phenomenona such as vector meson dominance and confinement.”

  6. Peter Woit says:

    Brathmore,
    See my above comment in response to Mitchell Porter. I don’t think any of those 2005 arguments for string theory have held up very well (as opposed to the counterarguments I spent a lot of time making back then, and don’t want to repeat now).

    In 2005 “string theory spinoffs” were a popular topic among phenomenologists, but none of that worked out and that sort of thing is now quite unpopular. I suspect that, like Kaplan, if Nelson were still with us she would now have have a more skeptical take on string theory than in 2005.

  7. James says:

    Susskind may be a jerk, but I always understood that yelling at the speaker at a physics talk is fairly common.

  8. Peter Woit says:

    James,
    In my experience, yelling at the speaker in physics talks isn’t common at all. But, in any case, Kaplan’s accusation seems to be that Susskind was doing this just to non-string theory speakers (terrorizing them by yelling at them that their work was bullshit).

  9. suomynona says:

    @Brathmore:

    Point 3 is demonstrably false. See for example doi.org/10.1103/PhysRevD.9.850 and its references and citations. Absolutely no mention of anything stringy as motivation here. Sure, the more recent work mentions string theory’s extra dimensions, but investigations into possible violations of gravitation’s inverse square law have a long history irrespective of any string-based inspiration.

  10. Peter Woit says:

    Brathmore, suomynona,

    To get an idea of the nature of the widespread hype from that era, take a look at this 2000 NYT article about how “Physicists Finally Find a Way to Test Superstring theory”
    https://www.nytimes.com/2000/04/04/science/physicists-finally-find-a-way-to-test-superstring-theory.html
    and subsequent Physics Today pieces “Large Extra Dimensions: A New Arena for Particle Physics” in 2002
    https://physicstoday.scitation.org/doi/10.1063/1.1461326
    and “The case for extra dimensions” in 2007
    https://physicstoday.scitation.org/doi/10.1063/1.2761818

    Most people at the time thought these models were bullshit, but sociologically they did manage to bring together the phenomenology and string theory communities, giving them both something exciting-sounding to point to and use to justify their funding. The whole subject disappeared without a trace once the LHC turned on and immediately, as expected, saw no evidence for such models. I don’t know if Kaplan at the time would have acknowledged this was bullshit, but he at least seems very aware of that now.

  11. Jim Eadon says:

    This is the funniest interview about physics I’ve read. And incredibly insightful at the same time, for example, pointing out intimidation. I wonder if the String Theory bubble is more threatened by people laughing at it, than by seriously-stated refutations. Which funding body wants to fund a joke? (I don’t meant to be provocative, it’s a genuine supposition). I wonder, is this level of derision of ST commonplace in physics?

  12. Peter Woit says:

    Jim Eadon,
    I think this level of derision about claims to get any information about a unified theory out of string theory is now very much commonplace in the physics community. You’ll hear it often privately and sometimes even publicly, not only about the fringe claims of Michio Kaku and Gordon Kane, but also about the claims being made for the “Swampland Program” for instance.

    String theorists are well-aware of this, and most now are careful to argue that they are no longer pursuing a unified theory, knowing that would not be taken seriously.

    It was somewhat remarkable that Kaplan referred to the currently popular “it from qubit” stuff as “literally bullshit”, since that is well-funded and taken very seriously by the powers that be.

  13. Attendee says:

    I attended one of these It from Qubit meetings. I dont work in that area and I was simply curious. I concur with Kaplan’s opinion. It is absurd to believe that quantum gravity can be obtained by appealing to quantum information. Why dont these guys first derive the standard model from quantum information before trying to figure out physics that is 17 orders of magnitude higher in energy?

  14. As someone who considers Particle Fever one of the finest science documentaries ever made, and without commenting on the much harder questions that Kaplan raises — I’ll just remark that the portrait of Lenny Susskind here is unrecognizable to me from 16 years of knowing him. Yes, Lenny is passionate beyond belief about whatever he’s currently working on, and blunt in his opinions. Yes, he often lets hunches run light-years ahead of either theorems or data. Yes, he may have been different in the past, or have some Jekyll-and-Hyde thing going on. But I never once saw him yell at or abuse anyone. On the contrary, I’ve been struck by his willingness to listen intently to any new idea, however seemingly farfetched and however junior the proposer, and to abandon his own ideas once he’s convinced they’re wrong.

  15. Bartek says:

    I just want to second what Scott said. I was a postdoc at Stanford for 3 years. I did not write papers with Susskind. I disagreed with Susskind a lot. I had exactly 1 (that is: one) situation when he was impatient with my questions and kind of brusquely told me off. Then, an hour later, he came to my office and apologized. That apology doubled my already deep respect for him. I’m very skeptical of what’s being said in this interview.

  16. A Stunned Reader says:

    A verbatim copy from the full interview transcript that’s linked at the beginning of the post:
    .
    “I am still of the attitude that I would do physics if I lived in a van. I really—I cannot help but do this. And those are the people who are going to come up with something. The people that cannot do anything else but this will do it in their sleep. We’re just addictively trying to figure things out. Those are the people.”
    .
    So basically only Kaplan and people that are just like him are the ones bound to make great breakthroughs and discoveries. Right. The level of self-involvement displayed throughout this interview is stunning.
    .
    Maybe next time he is interviewed he can tell us all about his grand breakthroughs, instead of spending the whole time bashing other people’s field of research by continuously repeating the very sophisticated argument that it is “all bullshit”. (The word “bullshit” appearing an impressive 8 times.)

  17. Peter Woit says:

    It may be that the Susskind behavior Kaplan reports was specific to the period of the late-90s at Stanford. It was a time string theory was not doing well, and phenomenologists were often very scornful of the subject, before the reconciliation between string theorists and phenomenologists caused by brane-world models. Stanford I think was a bit of an unusual case, with positions divided between SLAC and the university. At the university, the ideology of the string theorists was becoming more extreme, at the SLAC lab there would have been tension about funding work that had nothing to do with experiment. From what I’ve seen over the years in physics, the worst behavior comes about when people are fighting over grants/positions.

    In all the years I’ve seen talks by Susskind or ones where he was in attendance, I’ve never seen any bad behavior of the sort Kaplan reports. On the other hand, I have heard a vast amount of complete bullshit from him at such talks…

  18. Leo says:

    A long time ago I got really pissed at Susskind’s demeanor towards anything that was not his research, I’m glad I finally have an opportunity to show it:

    Please watch the first minute of this video

    where I believe he shows his true colors. Also, before anyone says he is being sarcastic, consider who he is talking to (mostly string theorists at Santa Barbara) so he is preaching (Bill Unruh calls him a preacher) to his quire, where he feels safe and comfortable to make such claims.

  19. Peter Woit says:

    Leo,

    About Susskind’s claim that
    “If you’re not working on eternal inflation you’re a blooming idiot and I can’t help you.”
    it has always required a great deal of self-control on my part to not say things like
    “If you are working on eternal inflation you are a blooming idiot and I can’t help you.”

  20. Interested amateur says:

    What paper is Kaplan referring to when he says:

    Kaplan:
    [laugh] There’s a semi-famous paper in model-building in my field, particle physics. The semi-famous paper was written by Lisa Randall and Raman Sundrum, and so it’s just called Randall-Sundrum. And there was some geometric, extra dimension that could solve the problem with the Higgs without supersymmetry. And it was kind of—you know, it had problems but the picture was kind of cool.

    —the reason it had that mini crash the last year was because of Randall-Sundrum [laugh]—

    —because of this stupid paper. And Jeff Harvey was like, “What? What was so bad about”—Kutasov said, “It was not even the most interesting paper to come out that day.”

  21. Peter Woit says:

    Interested amateur,

    This one
    https://arxiv.org/abs/hep-ph/9905221
    9583 citations and counting

  22. Interested amateur says:

    Thanks Peter; that’s the paper I had in mind, but Kaplan’s claim that it was “semi-famous” and “stupid” made me think he was referring to another joint paper of Lisa and Raman, or that I was misinterpreting as serious his possible tongue in cheek humor at this point.

  23. Peter Shor says:

    Attendee:

    You say

    It is absurd to believe that quantum gravity can be obtained by appealing to quantum information. … Why don’t these guys first derive the standard model from quantum information before trying to figure out physics that is 17 orders of magnitude higher in energy?

    You can’t possibly figure out the Standard Model from quantum information. There are an immense number of different possible quantum field theories, and quantum information gives you no clue whatsoever as to which one is correct.

    But you might be able to figure out some properties of quantum gravity from quantum information (just like you’re able to figure out a few properties of classical physics from thermodynamics) even though I think it’s very improbable that you’ll be able to derive a unique, complete theory of quantum gravity from it. Still, figuring out exactly what quantum information tells you about quantum gravity seems like a worthwhile research endeavor to me.

    I have no idea whether the It from Qubit people know this and are indulging in exaggerated hype about deriving quantum gravity from quantum information merely to get more publicity and more funding, or if they have simply deluded themselves. If anybody has any clues as to the answer to this, I’d love to hear them.

    [In fact, quantum information has already shed some light on quantum gravity. The paper of Almheiri, Marolf, Polchinski, and Sully (AMPS) showed that Susskind’s “complementarity” hypothesis for how information escapes from a black hole was wrong, at least in its original form.]

  24. Peter Woit says:

    Interested amateur,
    The comments by Kaplan about what string theorists at Chicago thought of this paper are pretty unclear, I’m wondering if there’s a transcription error, or maybe he just didn’t clearly express what he was trying to say.

  25. Anonyrat says:

    Months after David Kutasov called Randall-Sundrum “not even the most interesting paper that came out today” , Kutasov, Shifman and Randall were co-organizers of the Conference on Extra Dimensions in Field Theory and String Theory, ITP, Santa Barbara, November 1999.

    In trying to find out more about that conference, I came across this parody, titled “Lobotomy”.

    http://insti.physics.sunysb.edu/~siegel/parodies/lobotomy.html

    The actual conference used “New” instead of “Extra”, and here is it is:
    https://online.kitp.ucsb.edu/online/susy_c99/schedule.html

  26. Attendee says:

    Peter Shor – Quantum Information relies on general properties of quantum mechanics I.e. statements that are true for any Hermitean Hamiltonian. And indeed, as you correctly say, one cannot use these general properties to learn about theories (such as the Standard Model) where there are detailed dynamics. An actual theory of quantum gravity would need to describe dynamics such as the evolution of the universe from a gravitational singularity or the nature of black hole singularities and the theory in the low energy limit needs to reduce to spin 2 GR. These are detailed and essential questions that any quantum gravity theory needs to answer and I think it is highly improbable that appeals to generic properties of every Hamiltonian system will yield insights into these specific questions (from your response, I expect you agree with this – I just wanted to clarify my comment).

    But, I agree that one can rule out silly fantasies such as Susskind’s black hole complementarity as being incompatible with the basic properties of quantum mechanics using arguments such as the AMPS paper. While this is useful, its utility as a tool to actually learn something non trivial about quantum gravity is highly limited.

    In the specific case of complementarity, it had always been clear it was a fantasy – Mathur articulated these arguments in the late 2000s. Moreover, if you actually tried to implement a physical mechanism for information transfer from a 3D object falling into a black hole info a 2D surface, you immediately ran into trouble (I.e. not enough time to couple degrees of freedom falling in to stuff going out).

  27. disillusioned humanities PhD student, saddened/amused by string theory says:

    From the interview: “So now that I’ve finally dug into it, I realize that—not that all humanities fields are bad. But it’s much more like a humanities field where there are the prominent people in the field, and they decide what’s interesting. And that if you impress those people, you can get ahead. But that dictates then what research is done. And they’re not going to discover anything in that context. They’re not going to get anywhere.”
    ———————–
    This is spot on. I am a humanities PhD student who, after much tribulation, realized it would be psychologically impossible for me to pursue a career in my field, because it is so full of exactly the type of bullshit described in this interview (and on this blog). It is uncanny how closely the pathologies of string theory, as far as I understand them, resemble the pathologies of most contemporary humanities disciplines. As far as I can see, they are basically identical, except that string theory is much more consequential, and so much more money/funding/fame is at stake, than in any humanities field.

    As a PhD student, gradually gaining enough expertise to evaluate the claims of professors in their field, and then realizing that at least 60% of them, and ~80% of the most successful, are intellectual frauds who routinely doctor evidence/repress inconvenient evidence/promote their “theory” without any sense that evidence is even necessary, sometimes subconsciously from long practice, but often in full awareness of what they’re doing–well, this is depressing, disorienting, and psychologically disturbing. I have been surprised to learn that some bright physicists have this same experience, with string theory, and I sympathize with them.

    For both physics and the humanities: the subject matter is important and worth studying, and can be studied in ways that produce knowledge rather than bullshit. The world, and PhD students everywhere who love their subject matter, deserve better than this bullshit!

  28. Peter Shor says:

    @Attendee:

    Maybe it was clear to you that complementarity was a fantasy, but there seem to be a whole lot of smart people to whom it wasn’t clear.

    And as for listening to Mathur … I believe people considered his theory of fuzzballs to be much more improbable than Susskind’s theory of complementarity, so of course nobody listened to him.

  29. Attendee says:

    @ Peter Shor: The situation with complementarity is actually quite amusing. Publicly, many people would tout that as the party line, though privately, quite a few people would admit that they didn’t know how it could work. This is not exactly a surprise since complementarity never had an actual mechanism (otherwise, AMPS would not have been able to rule it out). AdS/CFT was supposed to be evidence for complementarity – but this is not true. AdS/CFT is a duality – it describes (say) a 3D AdS space in terms of a dual theory on the boundary – i.e. – just a variable redefinition. It does not actually provide a mechanism to move information around.

    The community around Susskind is highly entertaining – for most of the 2000s they were engaged in solving the “measure problem” of eternal inflation that Peter mentioned above. In fact, there is no actual measure problem : given a Cauchy surface, quantum mechanics and General Relativity provide a sensible time evolution. Now the problem with eternal inflation is that the answer depended on the choice of initial conditions and thus one did not have universal answers like one did with classical inflation. These guys didn’t like that answer since it didnt fit with their anthropic philosophy and thus they spent over a decade trying to come up with a “solution”. This was of course silly since you can’t get around the fact that the solution to this particular Cauchy problem did not have an attractor. All of these people were considered “smart” 🙂

    I agree that fuzzballs dont seem like a plausible end result of gravitational collapse.

  30. Peter Woit says:

    disillusioned,
    While there are commonalities between the problems of string theory and those of other academic fields, I don’t think a broad brush analysis of the problems is helpful. I also disagree with Kaplan’s analysis that the problem is the power of leaders of the field to determine who gets jobs and what research gets done. That’s the way human society works, it’s the way all fields work at all times. And yet, some fields at some times are healthy and make progress (HEP theory up til the 1970s/80s, many subfields of pure math these days), while others are unhealthy and stagnant (HEP theory post mid 80s).

    The problem is to understand why the leadership of a field is failing at their job. In the case of HEP theory, there’s a complicated set of reasons for why this has come about (I wrote a whole book about it…). It always seemed to me that a solution to the problem needed to start with this leadership admitting failure and trying to change its ways in order to do better. Unfortunately, this shows no signs of happening in HEP theory (try finding somewhere in the mass of Snowmass reports anything of this kind), and the field seems likely to just continue its recent trajectory (giving up on the subject without admitting it).

  31. disillusioned humanities PhD student, saddened/amused by string theory says:

    Peter Woit,
    You say: “I also disagree with Kaplan’s analysis that the problem is the power of leaders of the field to determine who gets jobs and what research gets done. That’s the way human society works, it’s the way all fields work at all times. And yet, some fields at some times are healthy and make progress …
    The problem is to understand why the leadership of a field is failing at their job. In the case of HEP theory, there’s a complicated set of reasons for why this has come about (I wrote a whole book about it…). It always seemed to me that a solution to the problem needed to start with this leadership admitting failure and trying to change its ways in order to do better.”

    I agree with all of the above, and should have clarified this in my comment. It applies equally well to those academic humanities disciplines I am familiar with that are both floundering epistemically and have as their subject-matters phenomena/questions that one can in principle pursue knowledge about (which is not all humanities disciplines, and that’s fine).

    Of course, there are epistemic challenges distinctive to various humanities disciplines/subject-matters that aren’t present in physics (or any natural science). But, at least in my judgment, the central problem in these potentially-knowledge-producing humanities disciplines is exactly the failure of leadership that you describe in the case of HEP, if I understand your comment correctly (I have not had a chance to read your book). Because they too have made progress in the past, and aside from that, one can see in principle how they could make progress. The problem is that a critical segment of the most powerful/successful people continue holding on to “results”/methodologies that turned out to be demonstrably false/not productive of knowledge, and this in spite of by now reasonably well-established alternatives. If that is the (or a) problem in HEP, then it is shared with these humanities disciplines.

    Personally, I would say (again assuming I don’t fundamentally misunderstand the issues in HEP) that in both cases there is a failure to “care enough” about the truth/truthfulness, though I understand that others would not want to put it this way. Whether it is helpful to focus on these commonalities depends what one’s concerns are. I agree that when it comes to trying to improve a particular discipline, like HEP or history or anthropology, the broad-brush analysis is not the most productive (analytically or rhetorically) thing to focus on.

  32. @Peter Shor: It’s very hard for me to imagine any of the It from Qubit people I know disagreeing with the following paragraph of yours:

    But you might be able to figure out some properties of quantum gravity from quantum information (just like you’re able to figure out a few properties of classical physics from thermodynamics) even though I think it’s very improbable that you’ll be able to derive a unique, complete theory of quantum gravity from it. Still, figuring out exactly what quantum information tells you about quantum gravity seems like a worthwhile research endeavor to me.

    That’s why your next sentence…

    I have no idea whether the It from Qubit people know this and are indulging in exaggerated hype about deriving quantum gravity from quantum information merely to get more publicity and more funding, or if they have simply deluded themselves.

    strikes me as a both uncharitable AND unexhaustive list of possibilities!

  33. Peter Woit says:

    Scott,
    What’s disturbing to me is that the exaggerated hype problem here looks much the same (involving even much the same group of people) as the decades-old string theory hype problem which has done a huge amount of damage. In the string theory case most string theorists I know had reasonable arguments for the work they were doing, with the hype coming from a vocal and influential minority. The same thing seems to be going on now, with likely the same ultimate effect on serious quantum gravity research (sooner or later the hype collapses, those responsible claim victory and move on, leaving a toxic mess of confusion behind that convinces most everyone to give up completely on the subject).

    The next blog entry is good example of this. Joe Lykken (until recently deputy director of Fermilab, now head of the Fermilab Quantum Institute) is giving a CERN colloquium on Wednesday claiming that prospective quantum computer calculations of SYK models with around 100 degrees of freedom will be “experimental quantum gravity”. He did something very similar back in the early aughts, making bogus claims that the LHC would be testing string theory based on large extra dimension/SUSY models. This kind of thing leads one to uncharitable thoughts about his motivations and behavior, but more importantly, shouldn’t something be done about it? Shouldn’t the leaders of this field be held to some basic standard of responsibility?

  34. Peter: To say we have an analogous hype problem in quantum computing would be a titanic understatement (and as you’ve alluded to, QC hype and QG hype are even starting to intersect). Of course, I have spent years trying to fight QC hype on my blog—but I don’t manage to address even 10% of what’s out there, certainly not today. Does that mean I’m giving my tacit approval to the other 90%? Or that my colleagues who are careful in their own statements, but ignore the hype, are giving tacit approval to 100%? That seems like too high a bar, even while I vociferously agree with you that more needs to be done.

  35. Peter Woit says:

    Scott,
    I understand that you have your hands full with the QC hype and are doing what you can to deal with that intractable problem. In some sense the quantum gravity hype is not your problem, but is the responsibility of the part of the theoretical physics community working on quantum gravity.

    I’m trying to raise awareness of two issues:

    1. Claims that “we’ve finally found a way to do experimental quantum gravity” by doing calculations or experiments with some QM system that has a conjectural gravitational dual (one that has nothing to do with physical gravity) are bullshit, but are now being promoted by very prominent members of the theory community.
    2. We’ve seen this kind of hype before, often from the same people, and there never has been an effective way of dealing with it. Can we do better this time? Who is responsible for doing something?

  36. Peter Shor says:

    Hi Scott:

    My previous comment was undoubtedly phrased too strongly.

    But many of the It from Qubit people seem to be fairly confident that they can figure out how the quantum information escapes from the black hole just by looking at quantum information. Given that quantum information isn’t adequate to come up with the correct theory of quantum gravity, I don’t really see why they can be sure that quantum information considerations are enough to tell them that.

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