WMAP two-year data?

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  • #1
turbo
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Main Question or Discussion Point

Does anyone here have any information why the WMAP year two data has not been released? It's easy to assume that there have been some surprises in the data, but that's just human nature. The numerous breathless announcements of "precision cosmology" were a bit hard to take after the first-year results came out - the delay in the release of year 2 data is a bit unsettling?

Just another tease: This web page says galactic clusters and superclusters are preferentially superimposed over cool spots in the first-year WMAP data, implicating them in scattering of the background microwave radiation. Has this information resulted in follow-ups? I have been concentrating on vacuum energies and not following the WMAP/CMB field too closely.

http://star-www.dur.ac.uk/~ts/wmap/wmappic.html
 
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  • #2
Chronos
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Conspiracy theories abound on the delay in releasing WMAP year 2 results. The WMAP people are simply not talking, so take anything you see on the web with a healthy dose of salt. A few months ago the official word was [by Dr. Bennet, NASA head of the WMAP project]

"It's hard to predict when we'll have the new release, but we're hard at work on it and we have come a long way. We know that people are eagerly awaiting the results, but that also means that we need to do our work carefully. We will release the data without delay as soon as our team is satisfied that we have satisfactorily completed our responsibilities."

The second year data includes the polarization data. This is a labor intensive project and very sensitive to any systematic errors in data collection. There were also some apparent systematic errors in the 1st year WMAP data. Nothing of any major consequence but a distraction the WMAP team would probably prefer to avoid. It is not difficult to fathom why the researchers wish to resolve artifacts in the data. It is too important to include unnecessarily spurious data. They are trying to drain the swamp, not feed the alligators.

There were varying opinions on the SZ effect. Conclusions by the WMAP team were contested here
http://arxiv.org/abs/astro-ph/0305468
but largely supported by other researchers as evidenced by this more recent entry
http://arxiv.org/abs/astro-ph/0410280
 
  • #3
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I heard a member of the WMAP project give a talk about a month ago. Basically the analysis is just taking a lot more time then they assumed it would and results could be expected "any week now." But then he also reminded his audience "that's what I told everyone all last summer."
 
  • #5
Nereid
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If any PF member has the time, I think it would be a valuable contribution to indicate what the SZ (Sunyaev-Zel'dovich) effect is is, and what role good observations of it will likely play in constraining cosmological (and other!) models (Hint: if you love physics, you'll really love the SZE!).
 
  • #6
Chronos
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Here is the brief version of SZE
http://www.mrao.cam.ac.uk/~hjb26/thesis/node12.html [Broken]
Cosmological applications are discussed here by one of the leading researchers in this arena
http://arxiv.org/abs/astro-ph/0208192
 
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  • #7
Garth
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Thank you Chronos for those excellent links - that's the advantage of PF for you!

Is there any connection between the ZPE and the recently suggested anomalous quadrupole and octopole alignments with local features?

See "Is the low-l microwave background cosmic?"
http://www.arxiv.org/abs/astro-ph/0403353 , from the abstract:
The quadrupole plane and the three octopole planes are remarkably aligned. Three of these planes are orthogonal to the ecliptic at a level inconsistent with gaussian random statistically isotropic skies at 99.8% C.L., and the normals to these planes are aligned at 99.9% C.L. with the direction of the cosmological dipole and with the equinoxes. The remaining octopole plane is orthogonal to the supergalactic plane at >99.9% C.L. In a combined quadrupole-octopole map, the ecliptic plane narrowly threads between a hot spot and a cold spot over approximately 1/3 of the sky, and separates the three strongest extrema (in the south ecliptic hemisphere) from the three weakest extrema (in the north ecliptic hemisphere).
Garth
 
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turbo
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Garth said:
Is there any connection between the ZPE and the recently suggested anomalous quadrupole and octopole alignments with local features?
If the electromagnetic zero-point field of the quantum vacuum is the aether through which EM waves propogate, and if it can be polarized by matter, as I firmly believe, then we should expect to see local effects. Are the artifacts in the WMAP data consistent with the aether concept? I haven't had the time to explore that, but it would not be surprising, although it might be shock adherents of the standard model. To paraphrase Mark Twain, the death of the aether has been greatly exaggerated.
 
  • #9
Garth
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Thank you turbo-1, my mistake, my dyslexic computer should have typed, "SZE and not "ZPE" :blushing:

Garth
 
  • #10
turbo
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Regardless, it was a serendipitous error, and I have been thinking about it a bit. Matter accelerating through the quantum vacuum fields should experience black-body radiation (Unruh Effect). The Earth is orbiting around the Sun, the Sun is in movement through the MW, and the MW is in motion WRT the local cluster. The trick is, the Unruh effect is supposed to be a local effect arising from the acceleration of an object through the ZPE field, but how do you define a global reference frame against which to measure these motions? And ultimately, given a lack of a global reference frame, how do we differentiate acceleration from inertial motion? An object may be in inertial motion in respect to its local reference frame, but be in apparent accelerated motion with respect to another (equally valid) reference frame. This problem has some Machian properties that are making my head hurt. :yuck:
 
  • #11
Garth
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The Highlight from the GPB web page http://einstein.stanford.edu/ , 20th August 04, reported an anomalous force. I quote
"About ten days ago, we began to notice that while in primary drag-free mode, the ATC was requiring more helium propellant than planned to counter an unexpected force along the spacecraft's roll axis-that is, in the direction of the guide star"

Of course there may be a prosaic cause for this such as gas leakage or whatever; however the guide star IM Pegasi is close (about 7 deg) to the antipodean position on the celestial sphere of our Galaxy's velocity with respect to the microwave background?

Antipodean direction of Galaxy's velocity wrt CMB
RA 22 h 24 min Dec +18 deg

IM Pegasi:
RA 22 h 53 min Dec + 16 50 deg

Might the effect be some Machian inertial anisotropy caused by the Galaxy's motion relative to the surface of last emission of the CMB, which presumably can be identified with the entire universe's Centre of Momentum frame? In other words GPB is being "left behind" in some sense and therefore appears to be accelerating towards IM Pegasi?

Just a thought,

Garth
 
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