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Blogger Mark Wyman wrote on Feb. 7, 2010 @ 19:54 GMT
A new WMAP data and paper release is always a little Christmas for cosmologists. Among the latest set of papers based on seven years of operation, released last month, one concerning whether there are
any Cosmic Microwave Background Anomalies suggests that the WMAP team has an affinity for bowling. Why? Because they set ‘em up... and then the knock ‘em down.
A bit of background: The WMAP dataset contains the finest map we yet have of oldest primordial light in existence -- the first photons released after the Big Bang that were able to make it all the way to us, living over 13 billion years later. As a result, to say that people have pored over these data with tremendous care and effort is to understate the case.
The simplest models for the early Universe in the dominant inflationary paradigm predict that the fluctuations in the temperature of the light from the CMB will be well described by a Gaussian random field. Thus, one of the most intriguing things to look for in the data are deviations from pure Gaussianity, which would signal that something extra and interesting was going on in the early Universe. This can be exciting, but comes with a critical caveat: statistics can be an unfaithful friend to the eager data-miner. This is because a purely random field on which 100 tests are done will, on average, produce at least one result that is only 1% probable in the underlying model. Hence, any anomaly that is found in the data must be provably much rarer than any random fluctuation if one is to believe that it is truly a deviation from the theory.
Given human nature and the hopes of glory that rest in each of our hearts, perhaps what happened was inevitable. As time passed, various experts on the WMAP data began to uncover strange anomalies in those data that appeared, upon investigation, to be just the sort of rarer-than-random things that would be the mark of a real discovery: Right away, people noticed that there was an huge cold spot smack dab in the middle of the map. Then the map seemed not to have enough structure on the largest scales (in technical terms, it had anomalously low power in its quadrupole, and seems to lack sufficient correlation on wide angular scales) Then the quadrupole was found to align with the octupole, defining a special direction in space that was cleverly named by one of its earliest investigators as the “axis of evil.” And then two halves of the sky were found to have starkly differing levels of small-scale temperature correlation, a so-called power asymmetry.
It’s critical to note that these anomaly-discovering experts never included members of the actual WMAP team. The team was itself admirably impartial throughout the hoopla that attended each discovery, presumably well aware that approval from the team would be tantamount to a final verdict on the discovery and that dismissal without careful analysis would be irresponsible. Nonetheless, they have clearly been keeping close watch on these developments. This new paper is their long-gestated answer to all these claims.
In short, their result is negative: they don’t believe the anomalies are real. They reach this conclusion through a careful study of each one separately. First, they give a concise review of each anomaly and the opposing arguments regarding its significance. This gives the paper an almost Thomistic style; by the middle, I was half expecting a sed contra to pop up. Then, they improve and deepen the original analysis, taking into account other developments in the literature. In each case but one, they conclude that the anomaly is less statistically significant than it at first seemed, moving each out of the “rarer-than-random” column and onto the “almost certainly just a fluke” side of the ledger.
I’m sure you’re curious now to know what the last anomaly standing is. It’s a bit of a curious and technical one: a quadrupolar “effect” in the two-point power spectrum. That is, the way the temperatures of the map are correlated depends a bit on where they are located on the sky, in a pattern that has four distinct quadrants. However, before you start writing your paper on the asymmetric Universe, it turns out that even this Official WMAP Approved anomaly probably isn’t exciting evidence for new early Universe physics. The critical evidence disfavoring an early Universe origin is that the effect isn’t equally present in different frequency bands, which true CMB effects must be; and the preferred direction that the effect aligns is suspiciously similar to the ecliptic pole -- the direction in the sky picked out by our (and the WMAP satellite’s) orbit around the sun.
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All of which is very reasonable and proper, and a bit disappointing. I, like anyone, am always eager for the Universe to throw us a little loop, to find a bit of an Easter egg left from the Universe’s earliest days. But as the WMAP team points out in their conclusion, we humans are simply hardwired to discern patterns, so much so that we do it too well -- finding patterns where none really are. Their example, a fun tidbit with which I’ll close, is pointing out the appearance of the initials “S. H.” in the map, which is certainly (?) not evidence for new physics, unless Stephen Hawking has something very surprising up his sleeve.
this post has been edited by the author since its original submission
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Lawrence B. Crowell wrote on Feb. 7, 2010 @ 22:58 GMT
Of course you do have to rack them up and knock them down. Only that way can you insure that the universe is really as rational as you think it is.
Cheers LC
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Lawrence B. Crowell replied on Feb. 8, 2010 @ 13:43 GMT
The polarization of anisotropies and inverse Compton scattering signatures in the Sunyaev-Zel'dovich effect indicate stochastic fluctuations associated with inflation. This gives some weight to /\CDM which has the universe emerging according to a quantum fluctuation of a scalar field. This scalar field reached a minimum across the cosmological horizon length with slightly different coupling strengths to the local Ricci curvature. These anisotropies with the SZ shadows and polarizations are weak correlations to these much earlier processes in the universe.
The universe is a spacetime which is asymptotically approaching a de Sitter vacuum. Inflation was a sort of phase transition in the earliest universe where the structure was nearly de Sitter for a very brief period of time. The scalar field, or inflaton, cascaded down its field potential and induced this configuration. Upon reaching the bottom of this potential the inflation was “turned off,” and there was the phase of “reheating.” This reheating is analogous to the production of latent heat in a phase transition. Quantum uncertainty fluctuations in the field coupled with local regions of curvature, where this reheating had some measure of inhomogeneity, or as observed from a central location an anisotropy, that is frozen out in what we observe now. These are weak signature of early processes in the universe.
To take this to some greater extent, the de Sitter spacetime is a time dependent conformal equivalent of flat spacetime, or Minkowski spacetime. The conformal factor is what determines the cosmological constant or /\. Quantum fluctuations may determine the value of the cosmological constant, where this is a major problem in string theory and cosmology, so that the frozen out value we observe represents how the universe is a quantum fluctuation that has been frozen out by a quantum induced phase of fields. The quantum fluctuation of the field serves to change the phase of a system as do thermal fluctuation in 1st and 2nd order phase transitions (eg. gas to solid etc).
This is only the beginning. To probe further, we need to map the cosmic gravitational radiation background (CGRB), for in the early inflationary period quantum gravity decoupled from other fields in a manner analogous to the decoupling of radiation from matter 380,000 years after the big bang. Gravitational radiation would then carry stronger signals of the earliest moments of the universe. The trio of spacecraft designated LISA are a spacebased gravity wave interferometric system which may detect this radiation. In time we may be able to map the CGRB just as we have now the CMB.
Cheers LC
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Georgina Parry wrote on Feb. 7, 2010 @ 23:22 GMT
Thank you for pointing that out, I see it now. Are you sure its not be SK for Santa Klaus!
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Steve Dufourny wrote on Feb. 8, 2010 @ 12:14 GMT
Hello ,
If we resume the evolution and if we insert some parameters, thus we have a graphic for a synchronization.There at this moment here is the parameters
atoms 4%
Dark cold matter 22%
Dark energy 74%
more the hubble constant and the reionization and spectral index, all that thus give a graphic for fluctuations and the angle.
But that seems confusing about the density and the geometry and topology of our Universe.All that due to the evolution and the rotation of the spheres around the center of our Universe.
The density in an evolutive point of vue thus implies a sphere where the volume is correlated too.
The perception is different with these rotating spheres and if the mass increases thus the density too , thus the temperature on the line time evolves too.
The Dark energy seems just an error of interpretation of our evolution because several foundamentals are not considered about the evolutive mass and these rotations around the center of our Universe.
The expansion is specific and goes to a maximum volume, a contraction is possible after towards the perfect balance between spheres.Thus the perception is specific too with the rotation of those spheres.
It is so important to know where we are in this Universe and how we turn in fact around this center.
Best Regards
Steve
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Eckard Blumschein wrote on Feb. 10, 2010 @ 17:31 GMT
Since they did not find something mirror-symmetrical like OTTO I feel not urged to believe that the universe was invented by theoreticians.
Those who like humor might wonder why Magdeburg has been named Otto-Stadt:
Whether Lutz or Willy,
whether thick or thin,
the virgin (Magd on top of Magdeburg) is open
for all to come in.
Because Otto is too large,
the virgin divides him
in Otto the rider (Otto the Great, the first German emperor)
and Otto with vacuum (Otto de Guericke, half spheres).
Melody like
Since Frankfurt is too large,
it is divided into
Frankfurt/Oder
and Frankfurt/Main.
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Steve Dufourny replied on Feb. 10, 2010 @ 18:00 GMT
hihihihihi viva el humor ,
Super dear Eckard,
Friendly
Steve
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moy01 wrote on Feb. 18, 2010 @ 20:09 GMT
It may be a proof of the antropic principle: "Stupid Humans" or "Smart Humans"
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Steve Dufourny replied on Feb. 23, 2010 @ 09:48 GMT
Hello dear Moy 01,
The anthropic principle and the aim of the intelligence and conscious seem being a reality of the evolution, because the harmonization, the optimization, the improvement are in the ultim equation.
Thus indeed we can say what the humans are catalyzers of this truth, this universa love who builds this Universal sphere and its spheres( cosmologics and quantics)They turn and there is an aim.
But we are youngs and we make errors thus we must harmonize the foundamentals for the best interactions between lifes.
I d like insist on one point , the humans are not more important than a flower, it is the complementarity which is important, thus the anthropic principle seems just a part but an important part like all.
The stupidity seems a driving force of our Earth reality, just because we are youngs.
But the actual problem is simple, it is dangerous at this moment due to a bad governance and the criminality and the corruption.
The leaders of this planet MUST IMPLANT the real universality and implant the bases of the harmony, if not we are goind to add sufferings in fact.
Thus the leaders, take your responsability without fear of these people.
Some stupidities are dedicated to disapear in time space evolution.The frontiers, borders, the monney, the differences, the arms and weapons,the stupidities and others.....it is our future with or without our approvement.
What are the rules of humans, ....catalyzers of this love' building simply thus let's improve our global ecosystem and its harmonious interactions.
To be or not to be , that is the question......
Regards
Steve
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Steve Dufourny replied on Feb. 23, 2010 @ 11:04 GMT
All that can be resumed by "The humanity is like a rainbow, a diversity of colors united in the light ".....and "It is difficult to turn off a big fire with one water drop, nevertheless a whole drops makes Ocean"
The complexity returns to the simplicity .......
Regards
Steve
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Peter Jackson wrote on Mar. 9, 2010 @ 15:38 GMT
I think you have it moy01 with;
-It may be a proof of the antropic principle: "Stupid Humans" or "Smart Humans"-
The fruitless search for intellegent life in the solar system goes on.
The WMAP guys really ought to get out more. Those exact results were predicted by the model of discrete fields (DFM) some time ago, but still haven't been noticed. Hey Ho!
I even have a lovely picture of it. If anyone would like to see it, check out the super Hubble shot of Orionis.
To precee; Two major elements of the small scale CMB radiation come from the bow shock particles of the planet and heliosphere. (ask V1 and V2). These will give a quadroplolar asymmetry, with a major peak over some frequencies from the orbital vector (ecliptic pole). They will find the other peak at our helispheric vector bow shock (as we head through the galaxy at 45,000kph or so).
This signal has been part of the search for intellegent life.
Lawrence? Steve? You both have a head start. I hope you get there.
Peter
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songjoong sdfsd df wrote on Dec. 27, 2017 @ 07:18 GMT
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