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An explanation for hemispherical anisotropy in the CMB?

  1. Mar 13, 2015 #1

    Chronos

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    This paper, http://arxiv.org/abs/1503.03859, suggests a possible explanation for hemispherical anisotropy in the CMB based on non-commutative space time.
     
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  3. Mar 14, 2015 #2

    wabbit

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    This sounds interesting but I am surprised to see a NCG paper which cites Connes only once in its bibliography (and that is for a 1994 textbook - 1990 for the original edition I believe).
     
  4. Mar 14, 2015 #3

    marcus

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    Hi Chronos and Wabbit, it does sound interesting. I'm always interested in the people and the name Pankaj Jain rang a bell so I looked him up:
    http://inspirehep.net/author/profile/P.Jain.1
    He seems to be specialized in phenomenology and has several papers about dipole anisotropy, as if fascinated by the idea of cosmos having a large scale asymmetry.
    He has a good track record of publication and citation.
    And he got his PhD in 1988 from SYRACUSE which I think was where Ashtekar was at the time. Possibly an inspiring place at that time. After PhD he didn't bounce around much. After 1993 or so, he basically just settled on the faculty of an institute of technology (engineering school) in India and stayed there. He could be good. As a cosmology phenomenologist he doesn't necessarily have to master and employ the latest of Alain Connes results, he just has to get one idea and apply it to the cosmos and see if it fits.
    That's all superficial--people interest/human interest. I'll go look at the paper itself which is the real thing that matters. Sounds weird, doesn't it!
     
    Last edited: Mar 14, 2015
  5. Mar 14, 2015 #4

    marcus

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    I looked at the article and didn't get a favorable impression--but I'm not an expert so that doesn't mean very much. It seemed to me that this article is basically a WARMED OVER version of its reference [19]
    http://arxiv.org/pdf/1407.1714v1.pdf
    Noncommutative Geometry and the Primordial Dipolar Imaginary Power Spectrum
    Pankaj Jain and Pranati K. Rath July 8, 2014
    Dept. of Physics, Indian Institue of Technology Kanpur, Kanpur - 208016, India
    Abstract
    We argue that an anisotropic dipolar imaginary primordial power spectrum is possible within the framework of noncommutative space-times. We show that such a spectrum provides a good description of the observed dipole modulation in CMBR data. We extract the corresponding power spectrum from data. The dipole modulation is related to the observed hemispherical anisotropy in CMBR data, which might represent the first signature of quantum gravity.
    ===========
    It looked to me as if reference [19] was where they do their real calculations, and over and over, in http://arxiv.org/abs/1503.03859, they cite two seminal papers by other people [15] and [16] and then they immediately afterwards cite [17 - 19] which includes their own work [19]. That seems to be where the meat is. In this 2015 one they don't get substantially new results they just cite [19] and other sources.
     
    Last edited: Mar 14, 2015
  6. Mar 14, 2015 #5

    wabbit

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    Thanks marcus - more or less expected something like that based on my quick biblio check but was too lazy to do a more thorough investigation, and waited for someone qualified to step in:)
     
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