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Large Scale anomaly in Planck data

  1. Mar 21, 2013 #1
    Just watching tweets come out of the conference, apparently there is a large scale anomaly that has come out of PLanck . One tweet says challenge to inflation, another says could be pre big bang physics. Obvioulsy Im just reading tweets, so not sure whats real yet. But this could be exciting stuff.
    The papers are released in a few hours. So we shall see what this is really about.
  2. jcsd
  3. Mar 21, 2013 #2
    Hearing "amplitude of the vairations in the CMB are larger on one side of the sky than the other"
  4. Mar 21, 2013 #3
    Other sutff: dark matter: 26.8 % , 4.9% baryonic matter, 26.8% dark energy. Hubble constant = 67.15km/s/Mpc age of universe = 13.82 bio year, 3 species of neutrinos.
  5. Mar 21, 2013 #4
  6. Mar 21, 2013 #5
    Wow! Is there some link where one can have access to info from the conference?

    EDIT: Nevermind I just saw the other thread.
  7. Mar 21, 2013 #6
    So now the dust has settled a bit, the papers are out, if you go on the other thread I started on Planck results, you will see a link and to conclusions. The paper did not consider the results a challenge to inflation, but it did say the WMAP anomalies were still present.
  8. Mar 21, 2013 #7


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    The papers are here: http://www.sciops.esa.int/index.php?project=PLANCK&page=Planck_Published_Papers [Broken]. About 30 papers all told, however, only a dozen or so are really interesting. It appears the consensus on CMB anomalies is yep, they are there and we don't quite know what to make of it. It certainly implies some sort of new physics in the very early universe.
    Last edited by a moderator: May 6, 2017
  9. Mar 22, 2013 #8


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    I would say that the consensus is that we don't know, and more work needs to be done. It is very premature to talk about new physics at this stage at all.
  10. Mar 22, 2013 #9


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  11. Mar 22, 2013 #10
    26.8% dark energy?

    Typo? 86.2 or 68.2?
  12. Mar 22, 2013 #11
  13. Mar 22, 2013 #12
    From the cosmological parameters paper of the Planck collaboration:

    "If we accept that the base CDM model
    is the correct cosmology, then as discussed in Sect. 5 Planck is
    in tension with direct measurements of the Hubble constant (at
    about the 2,5 sigma level) and in mild tension with the SNLS Type
    Ia supernova compilation (at about the 2 sigma level). For the base
    CDM model, we also find a high amplitude for the present-day
    matter fluctuations, σ8 = 0,828±0,012, in agreement with previous
    CMB experiments. This value is higher than that inferred
    from counts of rich clusters of galaxies, including our own analysis
    of Planck cluster counts (Planck Collaboration XX 2013).
    One possible interpretation of these tensions is that some
    sources of systematic error are not completely understood in
    some astrophysical measurements. The fact that the Planck results
    for the base CDM model are in such good agreement with
    BAO data, which are based on a simple geometrical measurement,
    lends support to this view. An alternative explanation is
    that the base CDM model is incorrect.

    Our overall conclusion is that the Planck data are remarkably
    consistent with the predictions of the base CDM cosmology.
    However, the mismatch with the temperature spectrum at
    low multipoles, evident in Figs. 1 and 39, and the existence of
    other “anomalies” at low multipoles, is possibly indicative that
    the model is incomplete. The results presented here are based on
    a first, and relatively conservative, analysis of the Planck data.
    The 2014 data release will use data obtained over the full mission
    lifetime of Planck, including polarization data. It remains
    to be seen whether these data, together with new astrophysical
    data sets and CMB polarization measurements, will off er any
    convincing evidence for new physics."

    I think saying "it is possibly indicative that the model is incomplete" is at the least an understatement, but it is also understandable given where is coming from.
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