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On the large-angle anomalies of the microwave sky

  1. Aug 24, 2005 #1

    marcus

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    This paper just came out this month

    http://www.arxiv.org/abs/astro-ph/0508047/

    On the large-angle anomalies of the microwave sky
    C. J. Copi (1), D. Huterer (2), D. J. Schwarz (3), G. D. Starkman (1) ((1) Case Western Reserve University, (2) University of Chicago, (3) Universitat Bielefeld)
    26 pages, 7 figures. High resolution figures, multipole vector code and other information can be found at
    http://www.phys.cwru.edu/projects/mpvectors/

    Have these issues already been discussed at PF? Is there a discussion of these authors' findings somewhere else on the web? There are two previous articles by the same authors, and a CERN Courier article. It looks like they are attributing part of the microwave background to NON-COSMIC, that is local, effects in the solar system neighborhood. This means they are revising the map of the COSMIC part of the microwave background. This would have serious repercussions on standard cosmology.

    So this recent paper, which also summarizes earlier work, is probably important and needs to be discussed.

    "[Abridged] We apply the multipole vector framework to full-sky maps derived from the first year WMAP data. We significantly extend our earlier work showing that the two lowest cosmologically interesting multipoles, l=2 and 3, are not statistically isotropic. These results are compared to the findings obtained using related methods. In particular, the planes of the quadrupole and the octopole are unexpectedly aligned. Moreover, the combined quadrupole plus octopole is surprisingly aligned with the geometry and direction of motion of the solar system: the plane they define is perpendicular to the ecliptic plane and to the plane defined by the dipole direction, and the ecliptic plane carefully separates stronger from weaker extrema, running within a couple of degrees of the null-contour between a maximum and a minimum over more than 120deg of the sky. Even given the alignment of the quadrupole and octopole with each other, we find that their alignment with the ecliptic is unlikely at >98% C.L., and argue that it is in fact unlikely at >99.9% C.L. We explore the role of foregrounds showing that the known Galactic foregrounds are unlikely to lead to these correlations. Multipole vectors, like individual a_lm, are very sensitive to sky cuts, and we demonstrate that analyses using cut skies induce relatively large errors, thus weakening the observed correlations but preserving their consistency with the full-sky results. Finally we apply our tests to COBE cut-sky maps and briefly extend the analysis to higher multipoles. If the correlations we observe are indeed a signal of non-cosmic origin, then the lack of low-l power will very likely be exacerbated, with important consequences for our understanding of cosmology on large scales."
     
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  3. Aug 24, 2005 #2

    turbo

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    I've been very busy this summer and missed this - thank you for catching this as bringing it to the forum. I have been working on the role of the quantum vacuum in cosmology, and critical to that is the concept that the microwave background is not cosmological, but local - the temperature of the quantum vacuum. A very critical test of this idea is that:

    1) Each of the movements of the Earth (around the Sun, Sun's path through the limb, limb's rotation around MW's center, MW's movement) will contribute to the anisotropies in the microwave background.

    and

    2) The small-angle anisotropies of WMAP2 will NOT agree with those of WMAP1, proving that the microwave background is local, not cosmological.

    We have been told for years that the discovery of the microwave background in 1965 is a stunning confirmation of the BB theory. This conveniently overlooks the fact that Gamow had predicted an afterglow of about 50 deg K, and physicists for the previous 70 years or so had predicted the temperature of the vacuum far more accurately (typically 2-6 deg K) using a Steady State universe model. Back in the 1800s, physicists were calculating the temperature of the vacuum with surprising accuracy.
     
  4. Aug 24, 2005 #3

    SpaceTiger

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    What do you mean by that? You mean there won't be acoustic peaks? Which value of l are you calling small angle? How will it change? Why will this imply a local interpretation?
     
  5. Aug 24, 2005 #4
    It seems obvious that if the very early universe were quantum mechanical in nature, then the very early regions of spacetime would have to be segmented in a correlated way. It would divide like a living cell in a very symmetrical way. The quadrapole axis would be heavily correlated with the octipole axises. And one would expect to lose correlation with larger L mulitpoles. But if the very early universe were in complete thermodynamic equilibrium, then there would be no correlation whatsoever and you'd expect not to see any multipole effects, just an even distribution. The question is whether these multipole effects are due to quantum nature of spacetime itself or of the first particles themselves. If spacetime did not expand fast enough, then one might expect that the early symmetry of the decaying first superparticles would have had time to dissipate to the point of equilibrium and be lost. But if spacetime expanded too much faster than the superparticles dissipated, then there would not be any ability for regions to interacts in order for quatrapoles to align with octipole. So the fact that we see the symmetry means that the particles expanded just as fast as the early superparticles could have dissipated. This kind of suggests that the first superpartices were themselves made of the very same spacetime that was expanding, or the multipole power spectrum is due to quantum gravity.
     
  6. Aug 24, 2005 #5

    Garth

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    There are two schools of thought; the standard model requires all the l modes of the CMB anisotropies to be cosmological. Even then there appears to be a deficit at the low l mode end, which apparently may be explained as a statistical fluke.

    The other school, turbo-1's, believes the anisotropies are all local and not cosmological at all.

    There is a third possibility, that is the cosmological CDM power spectrum data is contaminated at the low l mode end with a local signal, indeed many local sources such as the galactic plane have to be subtracted from the raw data so perhaps there is something that that masking process has missed. It seems that this paper is supporting this possibility. In that case the cosmological spectrum is definitely deficient at the low l mode end of the power spectrum.

    The consequences of this may lead to a modification of the standard model, particularly in regard to the size, and hence flatness or openness of the universe. The deficit may be explained because a closed universe would not have enough room for these very large anisotropies to form. However, on the other hand, the data, particularly the first peak, is consistent with a flat universe, i.e. one that is infinite.

    How may the low l mode deficiency and first peak be reconciled? By realising that angles are invariant under conformal transformations, therefore the data is also consistent with a conformally flat and finite model, such as a cylinder, cone or torus. The topology of our model, and hence the model itself may therefore have to be changed.

    Garth
     
    Last edited: Aug 24, 2005
  7. Aug 24, 2005 #6

    turbo

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    I mean that apart from the dipole-octopole anisotropies that have been heavily published, I expect that we will see areas only a few degrees in extent in the WMAP2 data that will not overlay accurately the WMAP1 data.

    These areas may be only a few degrees to us, but extended back 13+Gy, they will encompass immense areas of the universe that cannot possibly have conspired to change in concert over the course of a single year.

    If I am wrong, the concept that the CMB is local and due to the temperature of the quantum vacuum is totally bogus. I do not expect to be wrong. The longer the WMAP2 data is withheld the more I suspect that I am right.

    I will not elaborate for fear of having Marcus' thread locked and sent to oblivion.
     
  8. Aug 24, 2005 #7

    SpaceTiger

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    Well good, then you'll quit harping on it very soon. I've heard directly from members of the team that there are no surprises in the next release, they're just trying to be as precise as possible.
     
  9. Aug 24, 2005 #8

    turbo

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    That is the same statement that they have been releasing "officially" for years. I am not suggesting a conspiracy, but am troubled that WMAP1 was released fairly expediently, and WMAP2 has been logjammed for years.

    I do expect subtle differences that will demonstrate the locality of the CMB, not broad differences invalidating the dipole-octopole patterns found in WMAP1. I fully expect those to remain consistent.
     
  10. Aug 24, 2005 #9

    SpaceTiger

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    Yes, I'm disturbed about it myself.


    Sounds like waffling. If you want anyone to believe you and me to stop harassing you, you should put it together formally and submit it to the independent research forum. The above sentence leaves room for pretty much anything to validate your theory.
     
  11. Aug 24, 2005 #10
    Marcus these have been discussed many time before, it may pay to dig-out some of A Perez papers?..the latest paper you have actually linked to in 'Loop' thread, has some interesting idea's based on Insights by none other than Penrose, here is a small quote from this recent paper:
    http://www.arxiv.org/abs/gr-qc/0508100

    Perez Quote:It should thus be emphasized that this can be justified only
    if we declare that gravitation is, at the quantum level profoundly different
    from other degrees of freedom as only such posture would justify the different
    treatment awarded to both the gravitational and the scalar sectors in the
    present work. We have shown that a relatively simple proposal concerning a
    collapse of the wave function induced by some unknown mechanism, possibly
    tied to Quantum Gravity can in fact account in a transparent way, for the
    scale invariant spectrum that seems to fit very well with the observations.
     
  12. Aug 24, 2005 #11
  13. Aug 24, 2005 #12

    turbo

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    I'm glad to hear that. I'm confounded that anybody can be complacent about this delay. It is a publicly-funded project, after all.
    As I explained above, I expect that small areas of the WMAP2 data (no more than a few degrees across) will fail to overlay the WMAP1 data, and in fact, I expect some reversals in the CMB on small scales (mapped against the background of the visible universe). These small areas, projected back over 13Gy will encompass vast expanses of our universe that cannot have possibly been in causal contact with one another and cannot have possibly changed together in the course of a single Earth year. If this is true, then the WMAP data is not measuring a cosmological relic of the BB. It is showing us something local. If you want quantification, it will have to come from a bright young grad student or post-doc. I do not have the time or the math skills to give you a finer prediction.

    I have explained my reasoning before (CMB is the temperature of the quantum vacuum, and motion relative to that Machian frame causes the observed anisotropies) only to be called a crank and have the threads locked. I enjoy contributing to this forum, and have over 40 years of observational astronomy experience to share with folks, and am still somehow blindsided by the violent reactions that come about when I try to raise questions about astronomical observations in light of the Steady State universe that was good enough for Einstein, Hubble, Hoyle, and countless others.
     
  14. Aug 24, 2005 #13

    SpaceTiger

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    If I understand you correctly, then this corresponds to following rewording:

    You expect that there will be statistically significant time variability in the power spectrum at l <~ 50.

    Is that correct?
     
  15. Aug 24, 2005 #14

    turbo

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    Can you reword this again in English?

    I expect statistially significant variability over areas encompassing no more than a few degrees. I expect that the maps (+or- the baseline3.7K) will not overlay properly. This will demonstrate that the CMB is local, not cosmological, since variations over even a few degrees will ensure that the involved areas cannot possilbly be in causal contact!

    If WMAP1 does not overlay WMAP2 properly with regard to fine scales, this is a clear indication that the CMB is local and not cosmological. If these two data sets overlay perfectly WRT the background universe, then the CMB may in fact be cosmological. If they do not, there is no possibility that the CMB is cosmological. My model is absolutely falsifiable by this measure. Is the BB falsifiable by any such measure?
     
  16. Aug 24, 2005 #15

    SpaceTiger

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    Your language is imprecise. For example, what does it mean that they won't "overlay"? Statistical fluctuations will prevent the maps from being identical, but we can calculate the magnitude of those fluctuations. If it's well beyond what we would expect, then that would correspond to "statistically significant time variability", because the maps were taken at different times in the same regions of sky. Furthermore, the fluctuations would show up in the power spectrum, so that's where you would be looking for the variability. Finally, l <~ 50 is equivalent to saying "angles larger than a few degrees", but it's better for talking about the power spectrum because it's usually plotted in terms of the spherical harmonics instead of the angular scale. See here , for example.

    If you don't understand anything I said above, I suggest you research or ask me to clarify. You won't be able to successfully predict anything if you don't understand how it's being measured.
     
  17. Aug 24, 2005 #16
    turbo-1, three days before the WMAP1 data was about to go global, I was in a number of forums , many asked for some speculated guesses as to what the data may reveal, I was the only one who made reference to the probability of Polarized Alignment to the Galactic Plane, being a direct consequence of the method of WMAP reading and data gathering process?..I was laughed out of many a forum!..over the following months..things started to go my way.

    I am actually going to side with you on this one, but for slightly different reasons, and as soon as I get cosmological wind of the release of the data, I will be first in line to hazzard a guess..infact I am not going to wait as I have stated it many times, on many forums!

    We are immersed in a "dual-luminosity-function", wherby 'infalling' matter/energy to (upon) our locality is competing with the 'outgoing' radiative energy of our Solar-Galactic space will produce differing Photon Pressure readings, which have to be collated out from the WMAP data.

    Basically, there is a lot of Photons 'falling' into our Galaxy from the other Galaxies in the Universe, this competes with the outgoing Photons from all the Stars contained within our Galaxy. The total energy from infalling Photons has a "grip" signature, and even as our Galaxy moves through space, this pressure cause's a definate boundary, a seperation of CDM of Extra-Galactic space, and Hot Luminous Matter contained inside our Galaxy?

    There have been a number of papers over the last year that have made interesting inroads to non-singularity coupled Galactic evolutions.
     
  18. Aug 25, 2005 #17

    Garth

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    SpaceTiger what do your friends in the team make of astro-ph/0508047?

    Spin Network - Do photons interact with each other?

    Garth
     
    Last edited: Aug 25, 2005
  19. Aug 25, 2005 #18

    SpaceTiger

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    We have discussed these issues, actually, and I think the general attitude is skepticism, but not dismissal. I don't trust the statistics at all, particularly the significance of the alignments with the ecliptic plane, which reminds me of Arp's argument about the redshift distributions of nearby galaxies. Mostly, I just think this problem is being over-analyzed and, if I were in the field, I wouldn't touch it with a ten-foot pole. Whatever the significance, it's going to take more than the low-order moments of the CMB to convince me (and many others) of a non-trivial topology.
     
  20. Aug 25, 2005 #19

    hellfire

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    OK, but what about the Sunyaev-Zeldovich effect on scales < 1°? As far as I know the current correlation maps between clusters and anisotropies are poor. I assume that there are currently no reasons to think about a contamination of the first peak, but I don’t think that this can be discarded yet (...I remember we did already discuss this some months ago).
     
  21. Aug 25, 2005 #20

    SpaceTiger

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    "No surprises" is about all I could get out of them. They're pretty much sworn to secrecy until the next release.
     
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