Riordan Review of The Trouble With Physics

Lee Smolin’s The Trouble With Physics will be out soon in the UK, available February 22 according to Amazon.uk. This month’s Physics World has a very good review of the book by Michael Riordan, under the title Stringing physics along. Before his current incarnation as an historian of science, Riordan worked as an HEP experimentalist for many years, going on to write one of my favorite books about the development of the Standard Model, The Hunting of the Quark.

The review is very well done, and I especially like his description of string theory as not a theory, but “instead a dense, weedy thicket of hypotheses and conjectures badly in need of pruning.” The one place where I really disagree with Riordan, is where, like many other people, he explains the landscape issue and characterizes the problem with string theory as “it got caught up in its own mathematical beauty.” I don’t think that that’s the problem with string theory in general, and it’s certainly not the problem with the landscape arm of string theory research, which is explicitly devoted to the idea (see for example Susskind’s book) that the universe is something of spectacular mathematical ugliness.

Riordan goes on to make the claim that the way string theory is being pursued is of danger to science in general, since its continual evasion of any possibility of confrontation with experiment is of the same nature as “intelligent design”. Riordan writes “To me, string theory and intelligent design belong in the same speculative, unproveable category.” He ends with the recommendation “The Trouble With Physics deserves a wide, careful reading by all physicists concerned about the future of our discipline.”

This entry was posted in Uncategorized. Bookmark the permalink.

32 Responses to Riordan Review of The Trouble With Physics

  1. Keith Thompson says:

    Speaking of string theory:

    A cartoon.

  2. Thomas Larsson says:

    Science Fashions and Scientific Fact
    Michael Riordan
    Physics Today, August 2003, page 50

  3. woit says:

    Keith,
    That cartoon appears as a graphic in the Riordan article.

  4. Aaron Bergman says:

    To me, string theory and intelligent design belong in the same speculative, unproveable category, and Smolin apparently agrees.

    I think I’ve already used this line somewhere, but the fundamental difference between string theory and intelligent design is that string theory aspires to be science.

  5. woit says:

    Aaron,

    It’s not that simple, intelligent design also aspires to be science.

    I do agree there’s a fundamental difference: physicists should know better.

  6. Aaron Bergman says:

    Intelligent design pretends to do so, but we all know that it’s a facade.

  7. mclaren says:

    “,,,the fundamental difference between string theory and intelligent design is that string theory aspires to be science..”

    Alas, all pseudoscience aspires to be science. The difference twixt science and pseudoscience is that genuine science offers us a reliable guaranteed way of detrermining whether those aspirations are destined to be fulfilled.

    I keep asking the same question over and over again, but no one ever gives a credible answer — specify the experimental results which can be performed and will categorically disconfirm string theory’s predictions.

  8. Physicists should know better than to go too much past what the known math is saying. Philosophers can go wherever they want but the two disciplines should be kept more separate than they sometimes are.

    String theory is an attempt to link some fairly well known ideas. If the math to do this linking was well known, there’d be plenty of existing experiments to use. Adding extra stuff has to either explain new things or link old things. String theory seems to be overly trying to find new ways to verify old things that they hope to link to other old things some day. That’s kind of not all that important at this point (except maybe for public relations if it gets interpreted to be more than it is).

  9. mclaren says:

    “String theory seems to be overly trying to find new ways to verify old things that they hope to link to other old things some day.”

    Occam’s Razor.

  10. King Ray says:

    There seems to be an Orwellian (1984) aspect to string theory…

  11. amused says:

    I’m no string lover but have to take issue with Peter’s description of Riordan’ review as “very good”. From the review:

    “To evade comparisons with dross reality, for instance, string theorists have invoked an unseen “metaverse” of parallel universes corresponding to the “landscape” of 10^500 possible solutions that might exist”

    No, the landscape was a derived consequence of the theory, not something invoked or put in by hand to “evade comparisons with reality”. I’m sure most string theorists would have much preferred there to be a unique vacuum from which unique predictions could be derived. (And yes, I hate the landscape just as much as everyone else here, but that’s beside the point.)

    “But at least these ideas [loop quantum gravity and others] lead to firm, testable predictions by which they can be judged and – if found lacking – rejected. This is science”

    String theorists talk about the possibility of evidence for ST from cosmic strings — I don’t want to defend the credibility of that, but are the “firm, testable” predictions from LQG any more credible?
    Also, has it been shown that LQG doesn’t have a landscape problem similar to string theory? Has it been shown that LQG can be coupled to matter in such a way that a unique low energy effective theory is obtained which contains the Standard Model in Minkowski spacetime?

    Riordan writes “To me, string theory and intelligent design belong in the same speculative, unproveable category.”

    Having once called on string theorists to denounce Lubos for comparing ST to the theory of evolution (see here for the outcome 😉 ) I now feel obliged to denounce Riordan for comparing ST to ID, and also Peter for his uncritical reporting of it. Nothing good will come from this derision of the research efforts of serious scientists who are following their best judgement in a difficult situation. (Disagreeing with their judgement is quite different to mocking them by comparisons to the ID nutters.) Much better imo to keep hammering the stringers on their weakest point: the unearned hegemonic position of ST in formal particle theory, and the ills that follow from it. Such as string theorists having been hired into faculty positions “at a disproportionally high level not necessarily commensurate with ability in all cases” (to quote SLAC’s JoAnne Hewett), with some of them having chosen ST for the reason that “well, you know, that’s the way things are going” (an actual quote from an acquaintance of mine who switched to ST as a postdoc and got a good faculty position out of it. I can hardly blame him, he had a family to support…)

  12. woit says:

    amused,

    I didn’t intend to imply that I support everything Riordan writes, some of it is highly oversimplified.

    Actually I don’t think Riordan has it completely wrong to say that the Landscape arises from trying to avoid problems with experiment. The point is that simple string backgrounds have massless moduli fields and so predict new long range forces. If we saw these, this would be considered a huge confirmation of string theory. But they’re not there so people have constructed more and more complicated “backgrounds” to stabilize the moduli, leading to the landscape problem.

    As for ST and ID, I don’t agree with Riordan’s broad-stroke characterization of string theory, there are plenty of string theorists who are not fanatics and are intellectually honest. But there are also some who are highly intellectually dishonest and/or complete fanatics, as bad as any of the IDers (and this includes the two most prominent string theory bloggers). The anthropic landscape is no more based on legitimate science than ID is, and the way that research program has gained serious attention is disturbing.

  13. amused says:

    Peter,

    “The anthropic landscape is no more based on legitimate science than ID is”

    The anthropic landscape isn’t science in the usual sense, but is still quite different from ID. String theorists who work on this can reasonably claim that they are simply following to its logical conclusion what in their judgement was the best road forward in particle physics at the time. Our response to that would be that they were following what in hindsight was a bad road, and should try to find another one. But still, the fact remains that the anthropic landscape, although not science itself, was nevertheless arrived at in a reasonably scientific way by serious scientists. In contrast, ID is nothing more than a cover for promoting religion.

  14. Aaron Bergman says:

    It’s not as if string theorists put the landscape of vacua into the theory by hand; it’s always been there.

    I really think you should reconsider your characterization here. It is both false and tremendously offensive. What you’ve never seemed to realize is that the vast majority of the people working on landscape related things have done so for the express purpose of being able to make predictions. Now, you might not like their philosophy, and maybe you think they’re out to destroy science in order to save string theory, but to compare them to the intellectual dishonesty that is ID is something I’d hope you would think long and hard about before doing.

  15. Peter Woit says:

    Aaron and amused,

    Yes, the anthropic landscape was arrived at by standard deductive scientific arguments. The problem is what happened when people got to it. Many physicists have properly acknowledged that if your theory leads to something grotesquely ugly and complicated that can’t provide legitimate scientific predictions, you have to acknowledge that your theory is wrong and try something else, and that this is the conclusion the anthropic landscape forces on one. Some people refuse to acknowledge that this is what has happened, and I don’t see their behavior as fundamentally different than that of the IDers. They are giving up on the standard scientific method because it conflicts with their ideology.

    I’ve repeatedly made the scientific argument about why the anthropic landscape is not science, I don’t see any point to trying to make claims about what is in the hearts of either string theorists doing this or IDers promoting their views. That said, I think the recent flurry of press releases issued by universities about “tests of string theory” are every bit as dishonest as the press releases coming out of the Discovery Institute.

  16. Aaron Bergman says:

    I hope you would consider all the implications of what you are saying when you make comparisons with ID and ask whether such comparisons are necessary for you to make your arguments.

    Reading a bit more on the history of the ID movement might help, too.

  17. Thomas Larsson says:

    to compare them to the intellectual dishonesty that is ID is something I’d hope you would think long and hard about before doing.

    It seems much more fair to compare string theory to aether theory. The aether theorists were serious scientists – Lorentz won the Nobel prize and Poincare was one of his generation’s best mathematicians, like Gross and Witten. They had good reasons to view aether theory skeptics to be crackpots – aether theory is more or less an inevitable consequence of Newtonian mechanics and a finite speed of light, and the latter was experimentally proven beyond reasonable doubt. And they kept ignoring experimental data contradicting aether theory (Michelson-Morley, photo-electric effect), just like string theorists ignore experiments (no SUSY or extra-dimensions, positive cc contradicts AdS/CFT). It is an interesting empirical fact that the physics establishment kept believing in aether theory for 20 years after Michelson-Morley, i.e. for some five years after the crackpot patent clerk’s annus mirabilis.

  18. Thomas Larsson says:

    BTW, no LQGist can IMO can be compared to the top aether theorists.

  19. Peter Woit says:

    Aaron,

    I’m well aware of the implications of what I am saying. I really wish string theorists would seriously consider the implications of issuing dishonest press releases and pursuing pseudo-scientific research programs. This is doing real damage to the credibility of science among the general public.

  20. Aaron Bergman says:

    I’m well aware of the implications of what I am saying.

    I’m not sure you do. That’s why I suggested reading up on the history of the ID movement.

  21. 1uk3 says:

    LOL Peter when you compare string theory and its advocates to ID and its advocates you are just as ridiculous as certain string theorists who say that skepticism about string theory is analogous to “skepticism” of “darwinism”.

    Here’s what Lubos said once:

    “I think that the analogy between evolution and string theory is a rather fair one. In neither case, we have a practical method that would indeed allow us to kill the whole framework by a single observation. In both cases, there are hundreds of details that must be answered by a more detailed work. In both cases, someone’s emotional feelings that evolution is too cruel or extra dimensions are too religious are completely irrelevant for science’s opinion.”

  22. Peter Woit says:

    1uk3,

    Yeah, sure, the idea that some string theorists behave like intellectually dishonest fanatics is just ridiculous….

  23. Aaron Bergman says:

    I see. Reductio ad Lubos.

  24. Peter Woit says:

    Aaron,

    Lubos is often the best example, embodying many of the problems with the behavior or string theorists in a pure form, something one rarely sees in nature.

    But, even among those string theorists with blogs, he’s not the only example. At least he doesn’t have Harvard issuing press releases…

  25. Aaron Bergman says:

    You know, I’m not particularly interested in playing this game. We’re not talking about all the people you dislike or people who dislike you; we’re talking about whether it is fair to compare string theorists to proponents of intelligent design. This relates to very specific questions about motivation, methods and intellectual honesty. If you think those comparisons are appropriate, I think you’ve gone beyond the pale. If you just want to talk about how the bad bad people are doing bad bad things, then I’ve got better things to do.

  26. Peter Woit says:

    Aaron,

    I’m not making blanket accusations about “string theorists are as bad as IDers”, and I’m not making any judgements about who is “bad, bad” or likable or dislikable. You and others assure me Distler can be a charming guy, I’ve heard the same from many people about Lubos, and from what I’ve seen of Susskind, he certainly has his charm too.

    This doesn’t mean I don’t have serious problems with the scientific arguments that they make, and the tactics they sometimes employ in making them. There are well-understood norms of what an intellectually honest scientific argument is, and my claim is that at times these people have violated these norms, and all the evidence that I’ve seen is that they have done so for ideological reasons.

    What’s “beyond the pale” I think is not my views about this (which, by the way are shared by a sizable number of people in the physics community, not just Riordan, try asking around), but the kind of unprofessional behavior that some string theorists have decided to engage in. It’s doing a lot of damage to physics and to the credibility of the field. I’m not going to apologize for or stop pointing this out.

  27. Amos Dettonville says:

    Aaron, in view of your rejection of any sort of comparison between string theory and Intelligent Design (ID), it’s interesting to recall this from Smolin’s book:

    “In a recent interview, Susskind claims that the stakes are to accept the landscape and the dilution in the scientific method it implies or give up science altogether and accept intelligent design (ID) as the explanation for the choices of parameters of the standard model: ‘If, for some unforeseen reason, the landscape turns out to be inconsistent … as things stand now we will be in a very awkward position. Without any explanation of nature’s fine-tunings we will be hard pressed to answer the ID critics. One might argue that the hope that a mathematically unique solution will emerge is as faith-based as ID.’ ”

    Granted, he phrases this in the ambiguous form “one might argue”, but it seems clear that he is saying that, barring some kind of anthropic guide through the landscape, string theory is as faith-based as ID. Was Susskind “beyond the pale” in making that statement? Was Smolin beyond the pale for paraphrasing it as he did?

  28. Aaron Bergman says:

    I suggest you reread the passage. I don’t agree with what Susskind says, but there is no way to go from the text you quoted to the paraphrase, “barring some kind of anthropic guide through the landscape, string theory is as faith-based as ID.”

  29. Amos Dettonville says:

    Aaron, I’ll conceed that my paraphrase may have been off the mark. Susskind said “if the landscape is inconsistent” whereas I said “barring some kind of [should have inserted “consistent”] anthropic guide through the landscape”. Admittedly those are two different conditionals. On the other hand, I don’t think they are as unrelated as you do. Susskind’s “if the landscape is inconsistent” could be taken to mean different things, especially in view of his other statements, where he refers to faith in the emergence of a unique solution. From what would a unique solution emerge “if the landscape is inconsistent”? He also talks about having nothing to determine the constants of nature in that case… and it’s well known that he thinks the anthropic principle is the key to selecting from among the landscape of possibilities. But if the landscape itself is inconsistent (whatever that means), we wouldn’t need any kind of guide to select the right one. But anyway… disregard my paraphrase…. the point of my message wasn’t to paraphrase him, but to note that he made a comparison between string theorists (admitedly in a hypothetical situation) and proponents of ID. (By the way, I’m a bit surprised you didn’t also object to Smolin’s paraphrase, which if anything was even more tendentious than mine.)

    Forget the paraphrases. Just focus on what Susskind actually said. I see that you don’t agree with him, but my question was whether Susskind went beyond the pale by even suggesting that those who believe string theory may somehow produce a unique solution are comparable to proponents of ID. Do you disagree that this is what he implied? I guess it all depends on what he meant by “if the landscape is inconsistent”. It’s a rather muddled conditional, because even if the landscape IS consistent, surely there could still be theorists who think a unique solution could somehow emerge. In fact, we might more easily believe this if the landscape IS consistent than if it is not.

    Taken in its entirety, I admit that it’s not easy for me to assign a self-consistent meaning to Susskind’s remarks, but I do think it’s clear that he was, in some way, comparing how some string theorists might behave in some circumstances to how the proponents of ID behave. I suppose you could argue that his comments don’t apply, because his conditional (landscape inconsistency) is both counter-factual and inconceivable, but then what was the point of his comment? I think you have to admit that he was acknowledging that string theorists could end up seeming like ID proponents. Does this put him “beyond the pale”?

  30. Aaron Bergman says:

    Do you disagree that this is what he implied?

    Of course. He didn’t say anything close to that. What Susskind is saying (and he thinks he’s being clever — sigh) is that the universe looks fine tuned for the existence of life. Either we have to accept that the universe was designed for us or we have to accept some sort of multiverse and anthropic explanations. This is an old, old argument. Regardless, Susskind is using ID in a nonstandard way, referring to the design of the universe rather than the usual critiques of evolution. It is the people propounding the latter that are subject here.

  31. Amos Dettonville says:

    Here’s an exact quote:

    Susskind: “One might argue that the hope that a mathematically unique solution will emerge is as faith-based as ID.”

    Then I asked Aaron if he thought “Susskind went beyond the pale by even suggesting that those who believe string theory may somehow produce a unique solution are comparable to proponents of ID. Do you disagree that this is what he implied?”

    And now Aaron replies:

    “Of course. He didn’t say anything close to that.”

    This is fascinating, in a peculiar sort of way. We have two statements:

    (1) “One might argue that the hope that a mathematically unique solution will emerge is as faith-based as ID.”

    (2) Susskind suggested that those who believe string theory may somehow produce a unique solution are comparable to proponents of ID.

    Now, I will conceed that (1) and (2) are not identical, but I find it hard to accept that they are not even close.

    By the way, Susskind isn’t using ID in a non-standard way. The idea of intelligent design (of the universe) has been debated for thousands of years, going back at least to the ancient Greeks, and has been featured prominently in the thinking of many great scientists and philosophers. The adoptation of these arguments by anti-evolutionists is what is non-standard.

  32. Aaron Bergman says:

    Oh good. Now we can play definition games. Why don’t you google “Intelligent Design” and find me the first link that doesn’t deal with anti-evolutionism of some sort. (What you’re referring generally goes by ‘the argument from design” or the “teleological argument”. In modern usage, “intelligent design” almost invariable refers to the argument against evolution, and, more importantly, before we started playing Susskind-gotcha-games — isn’t it fun? — it was the subject of this thread.)

    Regardless, Susskind is not making a comparison between string theorists and IDers in general. What he is saying is that he believes that the belief in a single vacuum of string theory is not currently supported by the preponderance of the evidence, so that belief is “faith-based”. He hides behind a “one might argue” because he’s not actually making the comparison; he just thinks its clever to juxtapose the hope of some that string theory may have a unique vacuum with the faith that IDers have that a designer exists.

Comments are closed.