More on WMAP

In reference to my recent posting about the status of the WMAP experiment, an anonymous (but as far as I can tell, well-informed) source writes:

Hi Peter,

I am *not* a WMAP person, and would appreciate you not mentioning my name or my institution, but here is the story in the interests of keeping things sane:

1. WMAP is fine.

2. They are being very, very careful with their analysis.

3. Polarization foregrounds are difficult to model.

4. I doubt WMAP has detected GWs. Someone would have leaked that by now.

5. Note that WMAP does not have the sensitivity to detect the GWs predicted by inflation, it is hard to see how any simple, reasonable models could produce a GW signal much larger than that, and so a GW signal would be truly revolutionary if WMAP saw it.

6. The conspiratorial “Cosmology News” that you have linked to looks pretty slanted to me. They are talking about the famous missing power in low multipoles, discussed in the first year data release. Note that COBE also saw this missing power. IMO, I very much doubt this is due to systematics, as that site alleges, and statements that the team thinks –at the late date of 2004 — otherwise are almost certainly made up.

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16 Responses to More on WMAP

  1. Who says:

    DRL, you might be interested in this
    http://www.arxiv.org/abs/astro-ph/0508047/
    which just came out this month.

    it is by the same people and reviews earlier results,
    drawing stronger conclusions

  2. Quantoken says:

    hmm…VERY VERY INTERESTING!

    After reading the above paper. I completely changed my opinion regarding the mistery surrounding the WMAP data. I originally thought that it’s a known fact that many local astronomical objects do emit microwaves, so what’s big deal the data is contaminated by some foreground signal, which shows some characteristics ligned up with the solar system?

    But in reality it is a totally different story. Seeing something you do not expected see is one thing (which can be explained away by signal contamination), but seeing something you expected to see COMPLETELY MISSING from the data, is quite a different story, and it can not be explained away by data contamination!!!)

    Quote:
    “To conclude, using the multipole vector decomposition we have shown that the quadrupole and octopole of the microwave
    background sky are correlated with each other at a level that is excluded from being chance in excess of 99%. This comes about from a preponderance of peculiar correlations and is statistically independent of their observed lack of power. This observation is in bold contradiction to the predictions of pre-existing cosmological model, and argues against an inflationary origin for these fluctuations. In addition, there is strong evidence (again of greater than 99% confidence) that the microwave background at these multipoles is correlated with the geometry and direction of motion
    of the solar system. The observed signal is most unlikely to be due to residual contamination of the full-sky microwave background maps by known Galactic foregrounds.”

    Any comment?

    Note the authors are NOT the WMAP team members, who would be too timid to make such bold and politically incorrect statements!

    Quantoken

  3. D R Lunsford says:

    Thanks Who, that is a real paper.

    -drl

  4. The lack of correlations for angular scales above 60 degrees implies the smallness of quadrupole and octupole moments: see http://www.cerncourier.com/main/article/44/10/4.

    I have proposed an explanation in terms of many-sheeted space- time. The space-time sheets along which incoming photons arrive have finite size. For large angular separations it is probable that they arrive along different space-time sheets so that there is no correlation.

    See the subsection “Fluctuations of the microwave background as a support the notion of many-sheeted space-time” at http://www.physics.helsinki.fi/~matpitka/tgd.html#cosmo .

    Matti Pitkanen

  5. Artem Khodush says:

    Could this be explained by non-uniform distribution of mass in the universe? I.e. what if all the supposed dark matter is inside some giant black hole lurking somewhere, could that black hole affect CMB photons in a way to produce such anomalies?

  6. D R Lunsford says:


    Could this be explained by non-uniform distribution of mass in the universe? I.e. what if all the supposed dark matter is inside some giant black hole lurking somewhere, could that black hole affect CMB photons in a way to produce such anomalies?

    This is the problem with teaching and endorsing fantasies. Students start to think of fantastic (that is, absurdly unreal) scenarios instead of sticking to sane physics.

    The issue is that the data indicate an unexplained local contribution to the MB, after which the C in CMB is practically irrelevant, the BB plain wrong, and inflation an opium smoker’s pipe dream.

    -drl

  7. D R Lunsford says:

    This is off topic but important.

    Today we had an authentic physics miracle – once the eye was past New Orleans, the equally strong west winds pushed the storm surge back out to sea. It’s tempting to think of this as simple superposition of waves but wave motion is essentially different in even vs. odd spatial dimensions – in any case the equal and opposite winds on the south side of the eye tended to mitigate the storm surge.

    Now the amazing thing is, the storm turned right by just the right amount to be able to use the storm’s own rotational energy against itself. This is, to all purposes, a near miracle.

    -drl

  8. Artem Khodush says:

    The issue is that the data indicate an unexplained local contribution to the MB

    I dont’ get why it’s assumed local. Just because it’s aligned with ecliptic? Or are there other reasons in the article which I overlooked?

  9. D R Lunsford says:

    Because the “horizon”, the ultimate non-local, defines a (projective) metric, which in turn imposes an order – of magnitude – on influences. There are two scales – cosmic and local – because of the cross-ratio, which essentially is a quotient – and is the basic invariant of projective geometry. The claim so far is that the MB is cosmic only.

    -drl

  10. D R Lunsford says:

    I see I misread your question – I actually answered the question “Why you can’t assume it’s cosmic”. To answer the actual question – if aligned with the ecliptic then, since the final radiation field can be expanded in spherical harmonics, there is a pre-defined relation between all the various multipole terms, because the symmetry is now planar and not spherical – a favored direction. That is, space is not isotropic. In fact the most interesting part of this work is that the octopole and quadrupole are aligned, with each other, regardless of the ecliptic.

    -drl

  11. Artem Khodush says:

    Thank you DRL for the explanation. Looks like I misunderstood the term “local” – actually it can be anything anywhere that defines a favored direction. And doing wild guesses is pointless unless I could put that in the equations, solve, and compare result, which I can’t. Sigh. Thanks again.

  12. D R Lunsford says:

    Well people are imagining bizarro worlds with complicated topologies instead of just admitting the simple answer, that not only does light fall – gravity glows.

    -drl

  13. island says:

    So, Einstein was right if the universe is rotating, then it has a center of rotation, and a center of gravity. If the assumption about the universe being unbounded can be demonstrated to be false, then the Copernican Cosmological principle takes a big hit and BB theory gets more realisitic applied to a universe that has volume when a big bang occurs without a singularity.

    I’ll buy all of that even if I did have to say it myself… ;)

  14. D R Lunsford says:

    “The Universe is rotating”

    With respect to what?

    How can you even WRITE such a sentence?

    -drl

  15. island says:

    I know what you’re saying, but it falls out of Quantoken’s quote, maybe as more of a figure of speach… or wouldn’t this result in quadrupole and octopole moments?

    In addition, there is strong evidence (again of greater than 99% confidence) that the microwave background at these multipoles is correlated with the geometry and direction of motion
    of the solar system.

    The pattern indicates a rotating universe, since this incoherence manifests via octopole and quadrupole components in a bound universe, so there should be a center of gravity at the center of the visible universe with the universe rotating as a black hole might… with respect to what… I have no clue.