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CMB anisotropy alignments

  1. Nov 27, 2012 #1

    Chronos

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    CMB Maximum Temperature Asymmetry Axis: Alignment with Other Cosmic Asymmetries, http://arxiv.org/abs/1211.5915, raises some interesting questions so I spent most of the day reading more papers [I need a hobby]. It is certainly curious that the dark flow, alpha gradient, and dark energy dipoles are so curiously well aligned. The CMB temperature anisotropy was the first suspect, but, it is not so well aligned with these other three. The dipoles, in galactic 'l' coordinates are located as follows:
    dark flow - l = 282
    alpha gradient - l = 320
    de dipole - l = 309
    CMB temp - l = 264.4
    The error bars on the first 3 [df, alpha, de] are 11-18 degrees, whereas the CMB dipole is rather precisely nailed down to under half a degree. Obviously, the infamous 'zone of avoidance' precludes fully random directional data from being collected in all of these studies, but, appears to be reasonably well taken into account.

    The CMB dipole is 'obviously' easy to explain, its doppler shift due to the direction we are moving through the universe. The others, however, beg to inject 'new' physics into cosmology - at very least overturning the cosmological principle. I'm admittedly uncomfortable with this prospect. I have difficulty shaking the feeling something other than 'new' physics is at work here. One thing that was immediately apparent is the distance scales probed by these studies widely varies. The dark flow study falls well short of z = 1, the alpha gradient data was split at z = 1.8 [implying a high end of < z ~ 3?], and the de dipole only reaches out to about z = 1.12. If we were to extend all these dipoles out to the CMB dipole scale [at z~1100], would they all align? If so, would this somehow connect these dipoles to our motion through space? That would be interesting to see, albeit the methodology is beyond my grasp. Just in case you have nothing better to do, references for the other dipoles are:
    dark flow - arxiv 0906.3232
    alpha - arxiv 1008.3907
    dark energy - arxiv 1206.4056
     
  2. jcsd
  3. Nov 27, 2012 #2

    Drakkith

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    Interesting. I didn't know there were other asymmetries out there.
     
  4. Nov 28, 2012 #3
    Sadly. I don't understand much of the stuff. I just started reading on "distance scale of the universe". Can you please provide a more laymen explanation of that stuff and a kick start to understand the data. Sorry for the noob request and thanks. :confused:
     
  5. Nov 28, 2012 #4

    Chronos

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    Basically they are saying you see different things depending on the direction you look into the universe. Galaxies move in a preferred direction, the alpha constant varies depending on what direction you are looking, and the expansion of the universe is faster in some directions compared to others. I find all of this objectionable. If you throw the cosmological principle out of play, you get a universe that is illgoical, IMO.
     
  6. Nov 28, 2012 #5
    Thanks a lot. I'll try to squeeze some time understanding and interpreting data's rather than reading laymen's interpretation and general knowledge of the cosmos.

    I've read something on galaxy eso 137-001 plunging toward the center of a3627. According to them. It is measured independent of the universe's expansion and does not change as distance increases. Sort of like a massive hidden gravitational attractor? Compared to other
    clusters.
    So if all data were corrected now and observed the effect to be real. What might be the highest provable explanation of such? Can we rule in dimensions predicted by superstring. A new physics, a gigantic unknown blackhole or error in data perhaps?

    Reading cosmology is like QP. Both observations are counter intuitive to some degree but interesting. You have to gamble "wisely" as my mentor's word but i never have the grasp to understand what he means.
     
  7. Nov 28, 2012 #6

    Garth

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    Chronos you might find this eprint in today's arXiv interesting: A structure in the early universe at z 1.3 that exceeds the homogeneity scale of the R-W concordance cosmology
    Your OP eprint suggests "extended topological quintessence", which is an inhomogeneous dark energy system minimally coupled to gravity, as a solution to the alignments coincidence. Perhaps, alternatively, there might have been more time at these high z regimes for inhomogeneities to form.

    In this case it would be another example for the set of anomalies that we have discussed earlier; Is There An Age Problem In The Early LCDM Model? and even earlier: Is there an Age Problem in the Mainstream Model?


    Garth
     
    Last edited: Nov 28, 2012
  8. Nov 28, 2012 #7

    Drakkith

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    I'm assuming that we aren't quite ready to throw out the cosmological principle just yet and that there may be some logical explanations that solve this issue.
     
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