An explanation for hemispherical anisotropy in the CMB?

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Discussion Overview

The discussion revolves around a paper proposing an explanation for hemispherical anisotropy in the Cosmic Microwave Background (CMB) based on non-commutative geometry. Participants explore the implications of the paper, its author, and its relation to previous works in the field.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant references a paper suggesting a connection between non-commutative space-time and hemispherical anisotropy in the CMB.
  • Another participant expresses skepticism about the paper's depth, noting a lack of citations of key works by Alain Connes.
  • A third participant provides background on the author, Pankaj Jain, highlighting his focus on dipole anisotropy and his academic history, suggesting he may have valuable insights despite not being up-to-date with all recent developments in non-commutative geometry.
  • One participant critiques the 2015 paper as a reiteration of earlier work, indicating that it does not present substantial new findings and relies heavily on previous publications for its claims.
  • Another participant acknowledges the critique and admits to having anticipated such a response based on initial bibliographic checks.

Areas of Agreement / Disagreement

Participants express differing views on the value and originality of the paper, with some finding it intriguing while others are critical of its contributions. There is no consensus on the paper's significance or the validity of its claims.

Contextual Notes

Participants note the reliance on previous works and the potential limitations of the current paper in providing new insights into the topic.

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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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).
 
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!
 
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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.
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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.
 
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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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