The Unraveling of String Theory

This week’s Time magazine has as article by Michael Lemonick about the controversy over string theory entitled The Unraveling of String Theory. It mentions my book and Lee Smolin’s, and there’s a quote from Sean Caroll. There’s the usual hysterical reaction from Lubos Motl: Time Magazine: Physics is a Sin.

Lemonick more or less gets the story right, describing the reaction of string theory critics to the landscape as:

It was bad enough, they say, when string theorists treated nonbelievers as though they were a little slow-witted. Now, it seems, at least some superstring advocates are ready to abandon the essential definition of science itself on the basis that string theory is too important to be hampered by old-fashioned notions of experimental proof.

Lemonick describes both Smolin and me as having worked on string theory. Smolin has done original research on the subject, but I certainly haven’t. I don’t agree at all with Sean Carroll that the problem is that not enough string theorists “take the goal of connecting to experiment more seriously”. Many of them take it very seriously, but the fact that it is a failed idea that doesn’t work is what has forced them into the landscape nonsense and other complicated, unworkable schemes.

The quote from me is a little bit out of context. I was making the point that physicists necessarily often start out with speculative ideas that are “not even wrong”, in the sense that they are so poorly understood that one can’t tell where they will lead, and that this is very much legitimate science. On the other hand, once a theory is well enough understood to see that you can’t use it to make predictions, if you keep pursuing it, you’re not doing science anymore.

Update: Tomorrow on Science Friday Ira Flatow will have Brian Greene and Lee Smolin on to discuss string theory. The September issues of Scientific American and Discover magazines have book reviews of Smolin’s book and mine. The Discover review is by Tim Folger and entitled Tangled Up In Strings; it begins:

In the mood for some no-holds-barred gossip or a nasty screed? Then start browsing the physics blogosphere, where some exceedingly smart people are spending an inordinate amount of time belittling one another. Alas, even this magazine has come under attack. The cause of all the commotion? Some nervy upstarts are questioning the validity of string theory, which is to physics what Wal-Mart is to retail: the biggest thing around, dominant for more than 20 years now. And woe unto anyone who doubts the orthodoxy….

The Scientific American review is by George Johnson and entitled The Inelegant Universe. Johnson notes one of his pieces for the New York Times six years ago carries what he now sees as an embarassing headline: “Physicists Finally Find a Way to Test Superstring Theory” (in his defense, this kind of headline is still appearing in over-hyped articles about string theory to this day). I’ve been a bit surprised at how friendly a reception Smolin’s book and mine have been getting so far from science writers. I think one reason for this is that many of them have repeatedly over the last twenty years written articles about string theory that repeat a lot of the hype promising imminent success in producing predictions. They’ve now been burned too many times and are very open to listening to the critics.

This entry was posted in Not Even Wrong: The Book. Bookmark the permalink.

101 Responses to The Unraveling of String Theory

  1. Eric Dennis says:

    A new informal fallacy:

    Take a position P on some controversial issue. Infer an obvious absurdity A by combining P with other propositions made by an opponent, even though you are aware your opponent believes ~P. Conclude that your opponent is asserting A and is, therefore, an incompetent fool whose arguments may be safely ignored.

    This fallacy might be called “Lubosing the Question.” Or perhaps “Affirming the Lubos.”

  2. Dick Thompson says:

    How about “The law of the excluded Lubos”

  3. A Friend says:


    I question your commitment to science – and academic scholarship in general. You have the good fortune to be a staff member of a well-funded and recognized institution of higher-learning, yet you *waste* your whole damn time trying to argue about stuff that is – in the final analysis – unarguable from a scientific point of view. String theory this! String theory that! … WHO CARES!! Everyone with some objective thinking capacity knows that string theory is still in its infancy – if you consider it to be a valid program in fundamental physics at all. That being said, it would *seem* you have nothing original to contribute other than what you have been arguing for the past ump-teen months… that string theory is not “genuine science”; yeah! we get it! Now do you want to spend your time repeating the same old broken record again and again!… or have you spent that position of academic priviledge trying to persue worthwhile research?

    … if so, what?…

    It would seem – and I say this as a friend, not an opponent – that you really don’t have much to contribute constructively to the academic landscape, and hence your real *research* agenda is to spend all your time trying to convince people like Lubos that he is wrong… What a waste of time and energy!

    Your Friend

  4. LostHisMarbles says:

    Just to be pedantic: ” … both Smolin and I …”

    What is timescale (and manpower/personpower scale) on which one expects to see results?

    Expt HEP hasn’t produced anything beyond the SM in 30 years. (The b, t quarks, W, Z bosons, tau lepton + neutrino all fit into SM.) The pentaquark wasn’t really beyond SM but didn’t pan out. Expt HEP consumes vastly more millions that all of ST (perhaps more in 1 year than all of ST in 30 years … even including the cost of Caribbean orgies with nude eastern European girls). Is it then not even wrong, time to try something else? Because basically that is the way expt HEP is heading … funding for ILC is by no means guaranteed. Attempts to develop new acceleration technologies haven’t gone beyond tabletop models as of yet. What to do?

    Complain about ST if it makes you feel better, but ST isn’t the problem.

  5. Chris Oakley says:


    I forgot to say – congratulations on getting a mention in Time magazine!

    I am not sure I approve of a magazine being named after a dependent variable, but it is at least a dimension that is known to exist.

  6. Who says:

    Marbles, you appear to begrudge funds to experimental HEP because for 30 years its results fit the SM. That counts as a confirmation of the SM. Presumably 30 years ago people did not KNOW that the Standard Model was so good that it would turn out to fit everything they could observe at accelerators for the next few decades.

    It’s clear the experimentalists acquired information by their work, while for 30 years most of the theoreticians explored multidimensional blind alleys. I think this is primarily because the string majority has not focused on major nagging problems such as the positive cosmological constant, dark matter, and gravity without prior metric. On the contrary, it drained attention from persistent central questions.

    Progress in these core areas (assimilating the positive CC, dark matter, geometry without prior metric) has instead been made by a relatively small number of non-string theorists, who have now reached the stage of making testable predictions.

    I have to say the quote from Sean Carroll was a laugh—what he said at the end of the Time magazine article:
    The reason so many people keep working on it is that, whatever its flaws, the theory is still more promising than any other approach we have.”

    Marbles you suggest saying
    “…Lemonick describes both Smolin and I…”
    which would be ungrammatical. To your proposed correction “pedantic” is an injustice to pedants.

  7. a says:

    I am happy that censorship could not prevent you from bringing our problems to a wide audience. But please make it clear that only about 1/3 of high energy physicists are string theorists: otherwise wrong messages like
    Peter Woit = string theorist
    in some future might become
    physics = string theory = shit.

  8. LostHisMarbles says:

    I don’t begrudge funding for expt HEP but I also don’t begrudge funding for ST. 30 years ago nobody knew what HEP would produce (expt or theory). When one says the last 30 years have been a confirmation of the SM, that’s the point — it takes years for expt to validate any theory.

    By the early 1980’s the SM had been put together and the W and Z discovered, the big buzzword was “unification”. A falsifibale prediction of proton decay was made, tested, falsified. The most obvious logical direction for the theory to take had failed. And so people searched for other ideas.

    The fact remains that today, funding for expt HEP is increasingly hard to come by. Even RHIC (an already built machine, admittedly nuclear phys not officially HEP), has uncertain funding. And over 30 years the majority of theory (i.e. ST) has gone down blind alleys. It’s easy to blame ST, but I expect the problems of HEP theory to persist until accelerators produce data beyond SM.

    Dark matter? How does one perform controlled expts with dark matter? (How does it behave as a function of pressure and temperature? How to do such an expt?) If you have falsifiable predictions, then set up an expt and do it. Don’t blame ST.

  9. Who says:

    The “dark matter problem” is to understand galaxy rotation curves and similiar related things about gravity. A pragmatic empirical approach to it would be to do the experiment which Bekenstein proposed a recent paper in Physical Review D.
    Phys.Rev. D73 (2006) 103513

    Marbles your reaction illustrates one source of the difficulty in theoretical physics.

    Dark matter? How does one perform controlled expts with dark matter? (How does it behave as a function of pressure and temperature? How to do such an expt?) If you have falsifiable predictions, then set up an expt and do it…

    OK Marbles, here is the experiment. Bekenstein has proposed it and it could be set up with available (Lisa Pathfinder) components. But if you try to matterize galaxy rotation curves–in a kind of reflex reaction–then I think you take us back into the cul-de-sac.

  10. MathPhys says:

    1/3 of all theoretical high energy physicists are string theorists? Is that an accurate estimate?

  11. AnonyMoose says:

    Peter, the discouraging replies above are unfortunate, but never mind your naysayers! I think you are doing a great job.

    Eric, I am not sure what you mean because I can not assess the sarcasm or lack thereof in your post. I am fairly sure that this new informal fallacy is not so new, I think you are referring to the strawman fallacy. Anyways I can not tell whether you are attributing this to Dr. Woit or to Lubos. Same with Dick Thompson. I don’t mean to nitpick but some of us could use clarifications.

    As for the critics, you who calls her/him self Peter’s friend. I think Peter Woit is committed to the scientific pursuit. You might think it a waste of time and energy to attack string theory, but then you might believe string theory to be a fringe position. Unfortunately, though string theorists may be in the minority, they are a large minority, and very vocal for that matter. Dr. Woit is merely struggling to remove this metaphysical dogma from legitimate science. And LostHisMarbles, who says there is any one problem? The HEP might not give us further success, but I would not consider it a complete waste. The HEP gave us more than string theory.

    And finally, Chris, Who, thank you for encouraging Dr. Woit in his quest. Time Magazine. At least that dimension exists! But maybe we’re not so sure of that! I mean time might not be manifested geometrically (as a dimension) after all, given that some theories of quantum gravity use 4-D spacetime as a mathematical model for a dynamic 3-D universe. (The theory of relativity may need to be changed according to the data to quantize gravity.) Maybe this is ontological speculation, but we will never know until further revolutions in physics. And we will have no revolutions in physics without proper experimentation.

  12. Scientific American has a George Johnson review of your book and Lee’s in the September issue.


  13. a says:

    MathPhys: my estimate 1/3 for the fraction of string theorists has one digit of accuracy. Do you think that 1/3 is too low or too high? It might be higher among US theorists, but my definition of “high energy physics” also includes japanese experimentalists, european phenomenologists…

  14. Nick says:

    The article is on the front page of _link_

  15. D R Lunsford says:


    You can go to or for free, but you need an ID and password to get into – I smell a rat.


  16. Chris Oakley says:

    Maybe God has reserved it until we learn to understand relativity better.

  17. Comm.Math.Phys. Santa Claus says:

    Hi Everyone,

    Merry Christmas! (albeit somewhat early). Go to Springer’s “Comm. in Mathematical Physics” website:

    and enjoy free downloading for 30-consecutive days!… starting today!

    Ho ho ho… now to return to the North Pole and package all those gifts for children everywhere! Ho ho ho…

  18. LostHisMarbles says:

    Submit a proposed experiment to run on LISA Pathfinder, to validate Bekenstein idea.

    Decades ago, expt HEP validated current theory (or discriminated between competing theories), and simultaneously produced new puzzles, e.g. in 1950s there were precision tests of renormalized QED and also discovery of strange particles, parity violation (tau-theta puzzle). In 1960s there was the finding of the predicted Omega-, also unpredicted discovery of CP violation. And so on. But now for many years there is only a validation of SM, but no discovery of new data beyond SM from the accelerators. As for the cosmological stuff, propose expts to test ideas like Bekenstein’s and get on with it. Never mind what the ST camp does.

    What is happening in HEP today is an accident of circumstance. Don’t blame ST for any of it.

    Mother Nature is fickle. La Donna e Mobile.

  19. Sailor Moon says:

    I hope that professors in hep-th like teaching; the public is catching on, and hep-th will be defunded, just like hep-ex.

  20. LostHisMarbles says:

    HEP-ex (I include RHIC) is suffering from defunding because it is expensive and does not produce “instant gratification” or visible profit ~ basically no new exciting discoveries for many years (and the legacy of Manhattan project has worn off). It’s not the same as getting lost in mysticism/mumbo-jumbo a la ST. But even so:

    a) I do not begrudge the funding of ST
    b) If there are worthy problems like dark energy, and ideas like Bekenstein and MOND, and devices like LISA Pathfinder which might be able to test the ideas, then propose an expt. Never mind ST.
    c) The problems of HEP-ex (or HEP) are not caused by ST.

  21. Sailor Moon says:

    Mr. Marbles:

    The situation in hep-th is caused by the problem in hep-ex, not the other way around.

    The Superconducting Super Collider was canceled in 1993 because Congress saw a poor “bang-per-buck” ratio for investments in accelerators. High energy particle physics based on accelerators is being shut down across the US; research is migrating to the EU and and China. The US ~might~ get a linear collider in 2018.

    Yes, exciting things are happening in experimental neutrino physics, but the theory for that was done 20-30 years ago. We know that matrix elements off the diagonal aren’t zero… People have speculated that that might be the case for years.

    You might not begrudge the money that goes to ST, but remember that string theorists have to convince ~somebody~ to pay the bills. They’re highly productive at filling up pages in the Physical Review, but do they have anything useful to say about the universe we live in? Or rather, would those dollars accomplish more if we spent them on nanotechology, bioinformatics, or any of the other glamour fields that are an increasing priority at today’s research University.

  22. LostHisMarbles says:

    Sailor Moon: Indeed the problems of hep-th derive from those of hep-ex. I have said so from the beginning.
    It is an accident of circumstance in hep-ex that no new physics beyond SM has been found for 30 years. But ST is not to blame for that.

    So ST fills up pages in Phys Rev and takes funding. It is always a matter of value judgement as to where the money could be better spent. Nanotechnology etc can survive just fine on their own merits. You think ST should be defunded? Others think hep-ex should be defunded (as was the case with the SSC). Hep-ex deserves its funding, but it is a hard case to make without fresh discoveries, (as I say, an accident of circumstance). Who decides what is worthy to pursue?

    Do NOT make the fundamental mistake of thinking that if ST is defunded, that the money will go to “more deserving” fields. When the SSC was cancelled, some condensed matter people thought that the money would go to their field. It did not. Instead there was a general cutback in science funding. Basically, “if hep-ex can tolerate an $8B cut, then other fields of physics (science?) can also learn to make a sacrifice.”

    Funding is not a zero-sum game. The research money can simply disappear.

  23. Sailor Moon says:

    Yes, research money can disappear. And it very well may.

    The long term economic situation in the US is not good. US government, corporations and households have been able to spend beyond their means because the dollar is the international standard currency; the US can print dollars and trade them for oil, dvd players and sneakers. The picture won’t be pretty when boomers leave the workforce.

    Yes, what the US spends for the Iraq War in a year could pay for decades of science, but it’s not clear that basic science gives as good a return on investment as it once did. Before the 20th century, people had no idea what matter was, what life was, or how the brain works.

    There certainly are things to learn, but there may never be scientific breakthroughs as profound as relativity, quantum electrodynamics, or the discovery of the double helix. Scientists can fill journals from here until the end of civilization, but that doesn’t mean that funding agencies will care.

  24. LostHisMarbles says:

    Sailor Moon, I will have to leave it to PW to figure out the fundamental point of your post. I really have lost all my marbles.

    I merely make the point that defunding ST will not improve matters for other branches of hep-th. ST may be mysticism/dogma/etc, not science as one would like to define it, but that is neither here nor there. Researchers in other fields (CC, dark energy, etc) will have to make the case for funding on their own merits.

  25. D R Lunsford says:


    That’s what they said in the 1890s about the incomprehensible data of spectroscopy. I think big progress is right around the corner. In fact I know it is.


  26. LostHisMarbles says:

    I do hope that big progress is right around the corner. I put it to you all that the way to find it is to go out and explore. Make models, formulate hypotheses, propose expts and carry them out. And **do this all on your own merits**. If ST contributes nothing to the effort, leave it be.

  27. John A says:

    Chris Oakley:

    I am not sure I approve of a magazine being named after a dependent variable, but it is at least a dimension that is known to exist.

    …except in the realm of the quantum where the magazine de-materializes.

    Yes. I am a geek.

  28. Antonio G Zenteno says:

    Sorry for changing the theme but it is very sad for me to notice the recent attack to this blog. Some minutes ago this blog was transformed with the typical sense of humor of this residual combination of irony with stupidity that many hackers have. In other circumstances this attacks are very less than superficial stupid games. But this blog is also a very notorious example of free-speech that is so fundamental for this communication system to survive.

    So i need to say that i am in complete disagreement with this ugly way of showing the deep trash of our society that can not support the minimal requirement of left the people opinions alive even if you does not agree with them.


  29. Ponderer of Things says:

    Hmm… Not a good week for Lubos.
    The same issue of Times that declares String Theory “not even wrong” (hmm, I wonder where they got that quote? Is Pauli that known among Times reporters? πŸ™‚ ) also featured a cover story titled “Who needs Harvard?”

    Double-whammy for poor Lubos…

  30. D R Lunsford says:


    Yes, I also saw that, and was reminded of the decline of the NY Times itself.


  31. Kea says:


    I wasn’t joking.

  32. woit says:

    Please stick to the topic of the posting.

    I suspect you followed Lubos’s link to this blog. The blog is fine, his link sends it through a site that translates it to “jive”.

    Ponderer + DRL,

    Time magazine is not at all the same thing as the Times, either London or NY.

  33. Ponderer of Things says:

    Oops, I meant to say “Time”, not sure why I said Times.
    I have magazine sitting right in front of me, sorry for confusing you, DRL.

    So, if a similar article is also featured in “Space” magazine, how many dimensions do string theorists have left? Is it 10-4=6 or 11-4=7?

  34. Antonio G Zenteno says:


    Yes, this was the case. So my position and the interlocutor of my message are completely clear.


  35. Kea says:

    Is it 10 – 4 = 6 or 11 – 4 = 7?

    The 6 comes from the dimensionality (over R) of the complex moduli of the 6-punctured sphere.

  36. D R Lunsford says:


    Yes that is true, I read the thing about Harvard in Time Magazine and was immediately reminded of the decline of the New York Times as a force for democracy, just as Harvard had been for truth (veritas). That Harvard would run off Glashow and hire Motl says everything. He’s the Jayson Blair of matter.


  37. z3 says:

    Scientific American Sept issue carries George Johnson’s sympathetic review of Lee’s and Peter’s upcoming books. The review is titled “the Inelegant Universe”, and made me laugh with its comparison of string theory papers to the robotic essay generator at, which randomly produces a different paper every time you reload.

    George now finds his own headline from the late 90s – “Physicists Finally Find a Way to Test Superstring Theory” – to be embarrassing. There is also a Burton Richter mention, as well as Hawking’s quote from Beijing.

  38. Heinz Neumaier says:

    The ancient greeks said that a man is a man when he shows four virtues: justice, courage, measure and wisdom. In this discussion, justice is to say that what cannot be checked is not science; courage is to say this out loud despite the critics, measure is not to denigrate the opponents more than (or even as much as) they do with you, and wisdom is not to be led to embrace other issues. In contrast to many of his opponents, Peter is not only right, he is also a great man. And he is an example to others.

    Peter, go on! What you do is needed in this world.


  39. Perhaps the fraction of Physicists indulging in String Theory is 1 / pi?

    Or maybe 1 / d where d is the number of actual spacial dimensions? In that case, if they are right, the percentage of them decreases…

    Congratulations in any case for the Time Magazine mention. All I’ve ever had there was a Letter to the Editor.

  40. JoAnne says:

    In two years, we will have 1-2 inverse femptobarns of LHC data. In 3 years we will have 10-20 inverse femptobarns. I predict that at that point, nobody will be talking about string theory anymore. As pointed out above, we have been deprived of data at the TeV scale for a decade now (due to the untimely and unfortunate demise of the SSC) and this has hurt us all tremondously.

    If the worst case scenario plays out, and the LHC discovers nothing, then that is the end of particle physics as we know it. And that includes string theory. They may think they are immune, but they are not – they will fall due to lack of funding with the rest of us.

  41. String Theorist says:

    JoAnne is mostly correct, but tenure is tenure, and we will write the history of theoretical physics, because nobody is better qualified to understand it than us.

  42. D R Lunsford says:

    JoAnne said:

    If the worst case scenario plays out, and the LHC discovers nothing, then that is the end of particle physics as we know it.

    I completely disagree with this pessimism. This is the mindset that created the monster of string theory to begin with. One never knows when a new idea will show up. The key point is to get a theoretrical explanation of electroweak symmetry breaking. Quantum gravity is a side issue in comparison. This explanation is not at hand, and an accelerator around the girdle of the Earth would not provide it. It has to come from someone’s head. Prediction: The Higgs will not be found. That will be the great result of LHC that will set people thinking again. The answer will come out of neutrino physics.

    My worry is that the data will be cooked by unscrupulous theory groups or simply misunderstood, as happened recently with WMAP 3 and Cooperstock-Tieu, respectively. The real damage done by string theory is the corrosive effect it has on scientific integrity in general.

    We need more historians and fewer geniuses.


  43. Kea says:

    Prediction: The Higgs will not be found.

    You can say that again! Can you repost those neutrino masses, Peter? I wasn’t joking.

  44. LostHisMarbles says:

    I think the only particle to date which was misunderstood is the muon. But possibly the data could be “cooked”. Find a bump, proclaim the Higgs. Does anyone recall the zeta 8.3 GeV ~ circa 1985? It was found by the Crystal Ball collaboration, promptly proclaimed to be the Higgs (the mass of 8.3 GeV didn’t bother anyone) — I think some people claimed it was supersymmetry — and it was then undiscovered in a second high statistics run and never seen again.

    I hope the LHC finds three bumps, the Higgs of the SM (boring), the Higgs of supersymmetry (hah!), and the Higgs scratch-your-head “who ordered that”?

  45. D R Lunsford says:


    You have a way with words πŸ™‚

    Remember the magnetic monopole? 1984 I think..I was a rosy-cheeked deluded youngster and was sure it was real πŸ™‚

    Do you do online discussions anywhere? I’d like to hear your rationale for supersymmetry.


  46. King Ray says:

    As for string theorists, how many years do they have to wander in the wilderness before they realize they’re lost? Looks like about 40…

  47. LostHisMarbles says:

    DRL- thanks for the compliment πŸ™‚

    Callan-Rubakov monopole ~ 1984 as I recall, catalysis of fusion (?) based on SU(2) group, but the effect does not exist in SU(5), wich was the GUT of the time.

    I have no rationale for supersymmetry. I merely threw that in to be a troublemaker. I should point out that eminent physicists like Glashow (not an ST person) expounded total nonsense about the zeta. See,B145,302

    Georgi et al suggested it as the lightest of a three-Higgs doublet no less

    I am sorry to disappoint you, but I do not do online discussions. I was looking for a reference to the “not even wrong” quote by Pauli, I stumbled across this blog, and though I realize it may be ego-deflating to PW, the fact that I am foolish enough to post anything here merely indicates that I have nothing better to do.

    I suppose I disagree fundamentally with much of the philosophy expounded here. I have no great faith in ST, but I do not begrudge the funding of ST. I couldn’t care less about the unravelling of any strings. The following statements may sound contradictory, but they are not mutually exclusive

    a) ST diverts scarce funds from other branches of hep-th
    b) Defunding ST will not make extra dollars available to non-ST research.

    If anyone has worthy ideas and testable predictions, suggestions for expts, you will have to procure the funding on your own merits.

  48. Chris Oakley says:


    If you think that the continuing belief that the universe must be 10-dimensional, supersymmetric and stringy does not hamper alternative ideas about the way the universe might possibly work, then you are quite wrong. This lunatic and chronic belief has up till now made it impossible for non-believers to get a word in edgeways. And if dissenters are totally ignored, then what chance do they have of getting academic jobs?

  49. LostHisMarbles says:

    The non-believers will have to succeed on their own merits.

  50. Thomas Larsson says:

    LHM, funding envy is not really at the heart of string theory critique, nor is proposing a better alternative necessary (although I have one πŸ™‚ ) . Criticizing string theory is really a moral imperative. This was best formulated by string theory ex-star Dan Friedan: “recognizing failure is an essential part of the scientific ethos”. If string theorists don’t recognize that their theory has failed, others will. This is inevitable and long overdue.

Comments are closed.