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Useful annotated overview of string theory literature

  1. Nov 6, 2003 #1


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    The following paper entitled Resource Letter: The Nature and Status of String Theory was authored by Donald Marolf
    at UCSB. It gives a useful annotated overview of string theory literature, both popular and technical.

  2. jcsd
  3. Nov 6, 2003 #2
    Yes indeed! I just read it , and came here with a link to the abstract :http://uk.arxiv.org/abs/hep-th/0311044

    It is great that recent interest in stringtheory and its obvious problems are being scrutinized by many, and this paper as you state gives a good foundation for where to go in order to understand the basis for directions.
  4. Nov 16, 2003 #3
    The Fabric of the Cosmos

    Hi physics boys,

    I think that you deserve to be insiders. Brian Greene has finished his second popular book, The Fabric of the Cosmos,


    I've read it and it looks great. There is some older material about string/M-theory in it, a newer material on cosmology (and stringy cosmology), inflation, the arrow of time, the speculations and facts on time travels etc., but also a great story of the space. Is space (and spacetime) a "something" or is it just a bookkeeping device to remember the relations between different events? Our answer to this question has changed many times as the centuries went.

    I especially enjoyed the chapters on quantum entanglement (explained using a story with Mulder, Scully, and a gift from the Aliens). This chapter explains almost all aspects of various interpretations of quantum mechanics, and I believe that it is written in a better and more honest way than all other books on this subject that I've seen so far. Another chapter explains how these correlations can be used for "teleportation" of the objects. Well, teleportation has become a serious scientific topic, although we can't expect that it will be usable as some science-fiction movies suggest.

    The book - a book that also contains a lot of up-to-date information about the experiments, the observations of the microwave background etc. - should appear on February 10th, 2004. I believe that all the people who enjoyed the books by Greene, Thorne, Kaku, Hawking, Gribbin, Gamow, and others should not forget about this new one! You will see why.

    Best wishes
    Last edited by a moderator: May 1, 2017
  5. Nov 29, 2003 #4
    Thanks for the info, lumidek! That sounds great.
  6. Nov 30, 2003 #5
    just reserved it at the local library and i'm #14 in the list
  7. Jan 27, 2004 #6
    Kaku has one coming out in Aprill, on Einstein and geometry - I saw it listed in a distributor's catalogue.
  8. Jan 27, 2004 #7
  9. Feb 24, 2004 #8
  10. Mar 7, 2004 #9
    oh well

    Well, another example of somebody who is no real insider (he comes
    from gravity but not from string theory) and so represents a biased
    reading list - the most important developments of the last 1-2
    years, namely the works of Vafa et al, are not mentioned, while
    subjects such as the plane wave limit and non-BPS states are highly
    over-emphasized. Moreover no mention of the important work of Douglas and others on D-geometry.

    As usual, focus is on areas deemed interesting and important by
    some, but not by all researchers, and mono-culture continues
    to be bread. In some way, such an article does more harm than good.
  11. Mar 14, 2004 #10


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    R.X. wrote:

    Are you referring to Greene or to Kaku here?

    Could you summarize the main ideas and results of this work?
  12. Mar 14, 2004 #11
    Neither, nor - the thread is about Marolf's review and this is what I meant - a quite biased selection of topics, with no clear idea why some subjects he presents should be more important than others that he leaves out.

    Since you brought up other names: what I wrote applies also, more or less, to Kaku as well.

    Douglas initiated a program to understand the quantum properties of D-branes, starting from the appropriate mathematical formulation (which is in terms of derived categories). This is a bit complicated stuff, but conceptionally extremely important, and I mean this physicswise. Since it is not fashionable to work on it, not much attention has been paid to this subject, but unfairly so.

    I would say that many if not most of those more phenomenologically oriented papers, on brane models and alike, are pretty off the track and sometimes even outright wrong, just because they do not take effects into account which we know from Douglas' work.

    For example, many papers assume (in the context of a given brane model), that a brane-anti-brane pair breaks supersymmetry due to the tachyonic mode between them. They use this to feed some degree of SUSY breaking into their models. But we known from Douglas' work (via his concept of flow of gradings), that if you take the quantum geometry of those brane properly into account, then the notion of what a brane is and what an anti-brane is, is not a universal notion but depends on where you are in the moduli space. It generically so happens that a naive supersymmetry-breaking brane-antibrane pair turns into a susy preserving brane-brane pair in some other region of the moduli space.

    In other words, from the effective action point of view, the naive brane-anti-brane system has a non-perturbative potential with a susy restoring minimum, somewhere in the moduli space.
    This is probably not what the unsuspecting brane model builders had in mind... and they cannot know it if they didn't read Douglas' papers.

    Summa summarum, it just doesn't make sense to attempt any sort of brane model building, without the knowledge of such effects. Admittedly, this is mathematically very complicated stuff, and this is why only few people know about it - most others go the easy way and ignore it.

    Marolf's review does not mention this conceptionally important subject, as well as many other's work. As said, he is not an insider of these matters and probably doesn't know better. A priori, one may just not care, but the effect of such a review is that newcomers to the field get a biased impression of what is important to study and work on, and what not.

    Certainly, what is important to study and what not,
    could be debated over and is to some extent a matter of taste, but there is a limit of what is reasonable, especially for a review which claims to be a guide to the field. For example, mentioning non-BPS states as an important subject while leaving out the whole of Vafa's recent work is just outrageous.
  13. Mar 14, 2004 #12


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    Many thanks for this helpful comment!

    I bet you would do many of us a real favor if you could similarly sketch the content of Vafa's recent work and what its importance is in your opinion.
  14. Mar 15, 2004 #13
    Hmm... it's almost too much to do so - best thing for you is to
    look up his list of papers in spires and check the citations yourself
    - this will guide you to some of the important works:
    http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=find+a+vafa%2Cc&FORMAT=WWWCITE&SEQUENCE= [Broken]
    Comparing to others you see from this that he is one of the most
    prolific and creative researchers (actually has always been but
    currently dominates the field of string theory).

    At any rate, here a few highlights:

    General theme: topological strings. Not only (often exactly soluble)
    toy models for things like large-N dualities, but they also capture
    the holomorphic content (BPS sector) of supersymmetric string and
    field theories; such as superpotentials and gauge couplings in N=1
    SUSY theories, plus an infinite sequence of certain gravitational
    couplings in the effective action.

    - This framework has allowed to more or less solve the chiral
    (holomorphic) sector of N=1 susy gauge theories and in particular
    to determine their vauum structure. Most interesting is that all
    of this can be phrased in terms of matrix models. This is work done
    together with Dijkgraaf and others.

    - Non-perturbative physics on Calabi-Yau spaces: mirror symmetry
    has been used for a long time to determine effects that are
    non-perturbative from the world-sheet point of view, but from the
    space time point of view this was mostly tree level - ie, genus
    zero in the perturbative expansion. This was useful for eg computing
    effective actions of N=2 and N=1 string theories.
    The underlying geometry was Calabi-Yau manifolds or "Seiberg-Witten"
    Riemann surfaces.

    Now the new works (culminating in hep-th/0312085) deal with the
    full genus expansion in the string coupling g_s, and this makes
    it possible to obtain results that are exact in the string coupling.
    All of this has also a close relationship to integrable systems,
    and this allows to write down some results explicitly. The underlying
    geometry is some sort of quantum deformation of the geometries
    indicated above; roughly, if a Calabi-Yau space or Riemann surface
    at tree level is given by f(x,y)=0, then the exact quantum geometry
    is characterized by a differential operator obtained by letting
    x,y become conjugate symplectic variables; ie: f(x,y) -> f(x,d/dx).
    The solution of f(x,d/dx) P = 0 is then the exponential of the
    all-genus free energy, or exact partition function of the theory!

    - In related very recent work hep-th/0312022, it was investigated
    what the theory looks like in the strong coupling limit, where g_s
    is large. It turns out that the relevant geometry becomes discrete
    and has some analogy to melting of crystals. Most interesting in
    this is the following: from the exact expressions one can infer
    as to what the relevant "geometries" are, one is summing over in
    (the relevant topological version of) quantum gravity.

    Recall that it is sort of a dogma that one should appropriately
    sum over background geometries in quantum gravity. The outcome of
    the work under discussion is that the relevant "geometries" are
    more general than what one usually calls geometry. [Actually from
    the string perspective this is not too much surprising: we know
    (esp from the work of Douglas et al) that in stringy D-brane
    geometry, more general objects than manifolds or vector bundles
    are relevant, rather sheaves and more general objects.]
    That is, while a naive quantum gravity person may try to sit down
    and sum over some "smooth manifolds", we learn from Vafa-et-al's
    work what the right things are to sum over; at least in the
    simplified topological context, where one can do exact computations
    and obtain explicit results.

    These matters are obviously of tremendous conceptional importance,
    but since the papers are not easy to read and require quite an
    effort to understand even for experts, I am not surprised that many
    people are not aware of them. It would have been the duty of Marolf
    when writing such a "ressource letter" to point this out to a larger
    Last edited by a moderator: May 1, 2017
  15. Mar 15, 2004 #14


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    Thanks a lot for this summary.

    I had once heard a talk by E. Mayr, a collaborator of Vafa, in which he summarized some aspects of the stuff related to the topological string that you mentioned. I will have to sit down and look at these things in more detail.

    One further question, though:

    I had asked Mayr about the role played by Matrix Models in these approaches and I recall that he pointed to a distinction between new, very new, old and very old Matrix Models. I think he said that the very new ones are essentially the same as the very old ones!

    All this pretty much confused me, because apparanetly I don't know all flavors of Matrix Models. What I know and understand is the BFSS model and the IIB (IKKT) model.

    What other Matrix Models are there and how are they related to BFSS and IKKT?
  16. Mar 15, 2004 #15
    For example the Kontsevich model, which is among the simplest MM that have a relation to TFT. Otherwise, have a look at the original papers of Dijkgraaf-Vafa for matrix models versus N=1 Yang-Mills, and to the recent paper on the topological vertex for MM describing various other TFT.

    Actually much more could be said about all of this- I just bring this up in order to point ppl to really interesting and promising things to look at, rather than see them being mislead to exhausted, or otherwise not particularly interesting subjects.

    BTW, you probably meant P.Mayr and not E.Mayr, der Genauigkeit halber !
  17. Mar 15, 2004 #16


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    R.X., I am intersted in what you said about Douglas and his analysis in terms of derived categories. I did a search on the arxiv, and found several of his papers, but in order to understand them better I would like to work through an introduction to this branch of algebraic geometry. Do you know of one you could recommend? FYI my background is in algebraic topology.
  18. Mar 15, 2004 #17
    Well I am no mathematician and I can't really point out a good reference to derived categories -
    however, most of what is necessary in the physics context can be gathered from Douglas' lectures,
    eg for the more mathematically inclined see:

    BTW what I wrote about SUSY breaking (or rather, the difficulty of achieving this with brane models)
    is what the authors of the second paper write in the last section.

    Moreover you may find some works of Lazaroiu useful:



    BTW He happens to be now at U of Wisconsin at Madison, potentially in your neighborhood...
  19. Mar 15, 2004 #18


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    Thank you so much for the links. I have printed off Douglas' 2002 paper and am studying it. I am also looking at Lazaroiu's earlier paper. Exciting times!
  20. Apr 25, 2004 #19


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    Barbon's survey of String Theory

    just out

    http://arxiv.org./hep-th/0404188 [Broken]

    J.L.F. Barbon
    Department of Physics, Theory Division, CERN Geneva

    "This is a rendering of a review talk on the state of String Theory, given at the EPS-2003 Conference, intended for a wide audience of experimental and theoretical physicists. It emphasizes general ideas rather than technical aspects."

    it's a concise review: only 12 pages and a select list of 46 references
    Last edited by a moderator: May 1, 2017
  21. Apr 26, 2004 #20


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    Barbon cites this earlier survey article
    http://arxiv.org/hep-th/9905111 [Broken]
    which is 261 pages and 757 references

    Large N Field Theories, String Theory and Gravity
    Ofer Aharony, Steven S. Gubser, Juan Maldacena, Hirosi Ooguri, and Yaron Oz

    Barbon is recent, and Barbon says if you want a more extensive overview than he gives, then there are 3 references---2 of them are the standard books and not AFAIK online.
    And the third is this huge online thing by Mssrs A,G,M,O and O

    I dont know why Barbon didnt cite Marolf's. Maybe he had objections to it similar to those offered by R.X. a few posts back in this thread.
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