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String theory is a complete scientific failure by Daniel Friedan

  1. Sep 26, 2006 #1
    "string theory is a complete scientific failure" by Daniel Friedan

    to make it clear, I am quoting Daniel Friedan, a former string theorist at Rutgers from hep-th/0204131

    "The long-standing crisis of string theory"

    "String theory has no credibility as a candidate theory of physics.
    Recognizing failure is a userful part of the scientific strategy. Only
    when failure is recognized can dead ends be abandoned and useable
    pieces of failed programs be recycled. Aside from possible utility,
    there is a responsibility to recognize failure. Recognizing failure
    is an essential part of the scientific ethos. Complete scientific
    failure must be recognized eventually."

    Like Nietzsche's Death of God (the news of which require time)
    apparently string theorists like RX, Lubos, Witten, Randall, Kaku, Greene, etc., have not yet heard the news.

    Thanks bananan!
  2. jcsd
  3. Sep 29, 2006 #2
    Well, what can they say to prove incorrectness of ST? ST is mathematically satisfying, it only lacks experimental evidence.. for now.
  4. Sep 29, 2006 #3
    Dear bananas,

    it is usually the failed physicis who proclaim that their field of
    research has failed, rather than themselves. The one you mention
    too has completely decoupled from research, and what he proposes
    in the paper (the lambda model if I recall correctly), suggests
    that he has little idea what has been going on during the last 10+
    years. In particular we know very well that the world-sheet is not
    fundamental, and conclusions drawn from this perspective are very

    That string theory did not provide so far a derivation of the
    standard model and an experimentally testable prediction, is known
    to everyone, hardly any news, and not argued against. This expectation
    has clearly failed so far, but this does not mean that string theory
    as a theoretical field of research has failed; quite on the contrary.
    What is suppressed in all those statements is that a *tremendous* amount
    of substantial results has been obtained, including insights in how
    gauge theories and theories with gravity work, as well in their
    mutual dual interrelationship. The progress in this direction was
    much more than was expected by most, and suggests that the ideas
    are on the right track. Any further progress should come by
    reformulating, augmenting and complementing the theory by new ideas,
    rather than eliminating it - or you'd need to eliminate gauge theories
    as well... To experts this is quite evident, but not to outsiders
    who cannot dinstinguish between what makes sense and what not, and
    thus too easily fall victim to those self-proclaimed critics.
  5. Sep 29, 2006 #4


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    When the Allied inteligence officers asked Heisenberg about the bomb, he told that he decided instead to bet for a nuclear generator because the bomb should prove difficult to manufacture before the end of 1944. Then the officers told him "but see, we are in 1945" and he answered: "Of course, if you had not used so many resources for the bomb, you had taken my laboratory in 1944 and even finished the war one year before".

    Or something so. The arguments about "insights" is similar: can anyone proof that these insights were in need of string theory?
  6. Sep 29, 2006 #5
    RX I want you to know I did read this and I'll formulate a partial response some time soon. I concede I do not know Daniel Friedman personally. I concede that I know he was at the Univ of Chicago, then moved to start and head a string theory research group at Rutgers. I concede I did not know he is a failed string theorist bitter with string theory. I concede the only reason I know about this paper is that Peter Woit quotes from it from Not Even Wrong.

    Daniel Friedman was a string theorist so he is hardly an outsider.

    However, I do think he has valid criticism of string theory in that paper. One of the goals of string theory would be to recreate the particle spectrum of the standard model, with calculation of particle masses from first principles. That goal has not yet succeeded.

    Daniel Friedman makes the point second goal is that string theory has not explained current physics, which includes general relativity and the standard model. Which has not succeeded.

    Daniel Friedman makes the point third goal is to make new predictions. Daniel Friedman points out that since there are an indefinite number of stable vacua moduli, and all physics depends on the specific vacua moduli parameters, string theory is not predictive and can never be predictive.
    Last edited: Sep 29, 2006
  7. Oct 13, 2006 #6

    I am new to string theory, and I have a question that is probably extremely naïve (and that has probably been asked and answered somewhere else).

    In former theories, like gauge fields, particles are "point-like" (which is the cause of divergences, some of them being solved by renormalisation).

    In string theories, apparently, the most elementary objects (below elementary particles in the hierarchy of material structures), strings and branes, have an extension.

    However, most things we know that have an extension, are "made of something".

    Is it therefore naïve to ask the question : "what are strings or branes made of".

    Is this problem similar in a way to the problem of ether, which started by the question that was naturally raised by Maxwell equations : if there really exist free electromagnetic waves, then these waves are vibrations "of what?".

    The original answer was that they were vibrations of an all-pervading substance called ether.

    The story finally ended by Einstein's claim : "ether simply doesn't exist. EM waves exist by themselves, they are not vibrations of something else".

    Will you give me the same answer : elementary particles are vibration modes of strings or branes, which are objects that "exist by themselves", and are not made of an underlying substance ?

    Last edited: Oct 13, 2006
  8. Oct 17, 2006 #7
    According to string theory the answer is that the strings are energy in quintessence. They are not divisible and cannot be broken up (except for annihilations).

    Strings also are the winding energies that determine the "size" of the universe by wrapping themselves around the calabi-yau manifolds.

    To put it short and simple, string theory says that its strings are the quintessence of science and it really does mathematically work. Although it is not proven expiramentally though. It does seem like an easy way out of this question (similar to string theory's evasion of quantum foam and universes smaller than the planck length) but being a TOE does require leniance in some areas.
  9. Oct 17, 2006 #8
    Well, you're bumping into a nasty bit of epistemology here.

    There very question "what is it made of" is tricky. We usually answer that one with describe it's constituent parts. Strings by assumption have none, so the question becomes void really.
  10. Oct 17, 2006 #9

    Today he is. But this does of course not matter, it's the arguments that count. I just wanted to mention that it is usually the people who are bitter for some reason or other, go around and tell these things. Just sit back and ponder about the underlying motivations why that preprint has been written, why NEW has been written, and why that preprint “Samizdat” has been written. People who are involved actively in research do not behave in this irresponsible way, as they have their own good reasons why they do their research, and so prefer to spend their time doing something constructive. This does not exclude having some doubts as well.

    True - but an abundance of other, often unexpected results have been obtained which are very non-trivial and this suggests that we are on the right track.

    Read what I was writing before - string theory is highy predictive, however not at low energies, so far. And whether the landscape really exists at the quantum level is by no means clear - I don't believe in it. Clearly we need to understand the theory better in order to say the final word on this.

    They are nothing but strings. They can snap into others, but that's it. They do not seem to be composed of anything else (although there are attempts in this direction, check for "string bits"). The point is there is no other device for "testing" them - there is no separate microscope that you can use to "see" constituents of a string. All what you can do is to throw in another string and have it scattered - this yields just the usual picture of strings joining and splitting up.

    That's a misunderstanding. Strings that wrap a CY would be ultra-heavy.

    Recently a very nice controllable toy picture of stringy quantum foam has been found, check papers of Vafa.
  11. Oct 21, 2006 #10
    From the answers of Dimitri Terryn and pibomb, I understand that we have indeed reached with string theory, the ultimate level of matter.

    I always thought there was such an initial level, to avoid a "regressio ad infinitum". Sorry, until I have really entered into the mathematics of the theory, I am left with trying to catch something of it with the help philosophical concepts.

    I was intrigued by the fact that something having an extension could be not made of parts. On one hand, point-like particles seem more satisfying from this point of view. But on the other, from what I read, the extension of the particle (string or brane) helps in solving the divergences problems that plagued gauge theories, and that prevented them to include gravitation, that was'nt renormalizable.

    Thank you for your answers,

  12. Oct 22, 2006 #11
    String bits aside, are not the points along the strings identified in string field theory? As the string functional is ultimately a function of infinitely many (countable) points on the string, a philosopher could argue, on epistemological grounds, that strings are a higher level concept and not at all fundamental . The open and closed string interactions, taking place locally at certain points, would seem to further fuel such an argument.

    A rebuttal to this argument, would surely follow your line of reasoning, in that there is no conceivable device we can use to "see" individual string points. This would likely appease those philosophers that place heavy emphasis on sensory input.

    Those not satisfied with the device argument may accept the string bit concept (IIB in the pp-wave background). Indeed, considering the string as an ordered array of partons is probably closer to what Bertrand had in mind. Even those philosophers not comfortable with infinity will find satisfaction, as discretized strings can be built out of a finite number of partons.
    Last edited: Oct 22, 2006
  13. Oct 22, 2006 #12

    This is identical to my line of reasoning. In fact this has nothing to do with
    "sensory" input some philisophers may like. It is a fundamental point in quantum physics that quantities one cannot measure in principle (ie, are "not observable") de facto do not "exist", ie do not have any objective reality. String theory is complete in the sense that there are no other, non-stringy objects one could use to interact with a string and thereby resolve its substructure. In this sense a substructure does not exist. One can only scatter strings with strings, and all what one would see (if one could manage this experimentally ;-) would be a tower of resonances, corresponding to the excited states of the string.

    This "completeness" sets string theory apart from other attempted theories of quantum gravity, for which matter fields are added as extra degrees of freedom "by hand", and which thus do not provide a genuine unification of particles and their forces. From this viewpoint I am slightly at odds why this forum is called "beyond the standard model" (which is a notion of particle physics) while most contributions deal with an attempt at quantum gravity which by itself does not naturally deal with particle fields in the first place.
  14. Oct 22, 2006 #13


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    Given the philosophical similarities here with the monadology of Leibniz, one could ask why String theory fails to take the step of Lawvere-Tierney in freeing axiomatics from the set theoretic noose.

  15. Oct 24, 2006 #14
    lol... let's better leave out philosophy...
  16. Oct 24, 2006 #15
    Since Strings is background dependent, how does string theory account for its underlying 10/11D spacetime manifold with which strings interact?
  17. Oct 24, 2006 #16
    It does not - the present formulation of string theory, as you and others including string physicists know and say, is background dependent, and finding a background independent formulation, or what else the relevant notion may precisely be, is one of the most important issues. No one says the theory is complete, and many people work on that.
  18. Oct 24, 2006 #17
    Since spin foam/LQG formalism can be extended to 11D SUSY SUGRA n=8, do you think that could help string theory with a background independent formulation? Ashketar's variables can be extended to 11D SUGRA.
  19. Oct 25, 2006 #18
    I plainly I don't have idea whether it would be helpful or not, as that approach has its own severe problems (which may or may not be overcome in the future). There may also be other kinds of background independent formulations that no one yet has thought of... at any rate my belief is that a crucial piece of string theory is missing, and to draw conclusions based on the current formulation, like whether a landscape exists or not, are premature. Only further research may tell.
  20. Oct 28, 2006 #19


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    Why don't people work on string field theory as much as they used too. It seemed the most natural and elegant formulation yet devised (and of course BI). Were the technical problems too hard to overcome?
  21. Oct 28, 2006 #20


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    I am just guessing here, but it seems to me that regular string theory has become so rich and mathematically interconnected that their are a lot of opportunities to do satisfying research and discovery that are open to hard work and a modicum of talent. And as I've been looking at string field papers on the arxiv for the last few years, SFT doen't. It's still at the major breakthrough stage where Sen's and Witten's work still sits out there and the ambitious post doc can't find any quick and handy hooks to push forward with.
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