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Supergravity paper on LHC-physics by Chris Austin

  1. Jul 12, 2011 #1

    "Rough estimates are presented to show that the bump at 1.7 to 1.9 TeV seen in ATLAS-CONF-2010-088 could arise from about 10^{30} approximately degenerate Kaluza-Klein states of the d = 11 supergravity multiplet in the s channel, that could arise from compactification of d = 11 supergravity on a 7-manifold with a compact hyperbolic Cartesian factor of intrinsic volume around 10^{34} and curvature radius an inverse TeV. A first hypothesis that the modes in the bump arise from a large degeneracy that restores agreement between the spectral staircase and the Weyl asymptotic formula immediately above the spectral gap gives a number of modes that is too large by a factor of around 60000. An alternative hypothesis that the modes in the bump arise from harmonic forms on the compact 7-manifold that are classically massless and acquire approximately equal masses from the leading quantum corrections to the CJS action naturally explains the slight reduction on a logarithmic scale in the number of modes relative to the first hypothesis, and predicts that the bump is spin 0 if the compact hyperbolic factor of large intrinsic volume is 7-dimensional, and a mixture of spins 0 and 1 if it is 5-dimensional or 3-dimensional. Even dimensions probably give too many modes. A provisional solution of the quantum-corrected d = 11 Einstein equations on a compact hyperbolic 7-manifold times 4 almost flat extended dimensions whose de Sitter radius can easily be as large as the observed value is considered, and a Horava-Witten boundary is introduced to accommodate the Standard Model fields."

    Any thoughts? Is this a good paper (I don't have the background to make such a conclusion)? But if it is, then I think it looks quite promising, that 11d SUGRA makes prediction in the LHC-realm. In my thoughts, this could perhaps lead to strings making predictions in the LHC-realm? :)

  2. jcsd
  3. Jul 12, 2011 #2


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    Schreiber, this is just a general comment on using arXiv.org.

    The way it is set up you can very quickly get an idea of the publication track-record and citation history of the author. This is not decisive, but it may raise questions or give hints. for example in this case go to the arXiv abstract and click on the author's name:


    (if you substitute grp_physics for hep-th you can see if there are any other papers in some other category, in this case there are none: these are the only Chris Austin papers)

    None of the seven have ever been cited except by Chris Austin himself. None have been published. There is no institutional affiliation. For whatever reason, they are from his home address in Cumbria UK.

    arXiv makes it very quick and easy to get a little background like this. Over on the right of the abstract page you will see a link that says "cited by". I make it a practice, when I encounter an author who is new to me, to make a quick check of past papers, cites, and institutional affiliation. As I say, there is no reason to think of this as decisive---but oddness can suggest questions or put one on one's guard.

    It is a 60 page paper, as I recall. I hope that someone here with an interest in the subject will have a look at it and help you evaluate it.
  4. Jul 12, 2011 #3


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    BTW Chris Austin is a regular contributor to the discussion at Peter Woit's blog "Not Even Wrong".

    Google [ "Not Even Wrong" "Chris Austin" ](with the quotes but without the brackets). You will get many hits.

    In person, on the NEW blog, he sounds cultivated, polite, knowledgeable, intelligent. It seems to me odd that his work would not be peer-review published and cited in the physics literature. There may be some reasonable explanation---and since I'm not interested in his particular field of research I must refrain from making any assessment of his work. Hopefully someone else will help you out there.
  5. Jul 12, 2011 #4
    Thank you for the advice Marcus. I am sorry if I have been spamming you with useless papers. I shall do my background-checking better, next time I will put up a paper in the forums.

    I can see that you've got a good point with his background, institutional situation etc. :)
  6. Jul 12, 2011 #5


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    No regrets! He can be a very good researcher just in unusual circumstances. It could also be a useful paper. Or perhaps not. The circumstances are not decisive. I support and respect your curiosity and the initiative you show in finding things!

    I hope someone else in closer contact with those topics will evaluate. We should not be too negative or we risk not finding something valuable.

    I only mentioned the background check because it is a resource which you have, when you work with arXiv. They make it very quick and convenient to get some perspective on the source of the paper and on its publication and cites. Another good thing about arXiv :biggrin:
  7. Jul 12, 2011 #6
    There are lots of supergravity and superstring models which, for certain parameters, would predict effects visible at the LHC; for example, hundreds of papers on "TeV-scale gravity". This paper I think is a respectable contribution to a rather neglected version of the idea.

    It has some resemblance to a much better-known class of models, where the extra dimensions form a "swiss-cheese" Calabi-Yau with a lot of "holes", we live on a braneworld near just one of the holes, and dark energy comes from purely gravitational interactions with braneworlds at distant holes. But here the extra dimensions are a compact hyperbolic manifold. Also, the author wants to locate the visible world on a boundary of the manifold, rather than on a braneworld in the interior of the manifold. It seems that Chris Austin is the only person on Earth exploring this combination of

    TeV-scale gravity + finite-volume hyperbolic compactification + visible universe on a boundary,

    which would be the main reason why his papers have no citations. I'm not saying they're perfect - research this complex, conducted in isolation, will almost certainly contain mistakes - and the particular observation he's explaining is probably just due to a few fluke events. But the guiding idea is a respectable possibility, it's good that someone should show what's involved in applying it to phenomenology, and as far as I can see this is all being done by someone who is technically competent.
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