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antoniseb
2006-Mar-16, 06:13 PM
There is new information on the WMAP website.

Blob
2006-Mar-16, 06:22 PM
Hum,

"Scientists peering back to the oldest light in the universe have new evidence to support the concept of inflation. The concept poses the universe expanded many trillion times its size in less than a trillionth of a second at the outset of the big bang.

This finding, made with the Wilkinson Microwave Anisotropy Probe (WMAP), is based on three years of continuous observations of the cosmic microwave background (CMB), the afterglow light produced when the universe was less than a million years old.
WMAP polarisation data allow scientists to discriminate between competing models of inflation for the first time. This is a milestone in cosmology. "

http://wmap.gsfc.nasa.gov/results

ngc3314
2006-Mar-16, 06:57 PM
Hum,

"Scientists peering back to the oldest light in the universe have new evidence to support the concept of inflation. The concept poses the universe expanded many trillion times its size in less than a trillionth of a second at the outset of the big bang.

This finding, made with the Wilkinson Microwave Anisotropy Probe (WMAP), is based on three years of continuous observations of the cosmic microwave background (CMB), the afterglow light produced when the universe was less than a million years old.
WMAP polarisation data allow scientists to discriminate between competing models of inflation for the first time. This is a milestone in cosmology. "

http://wmap.gsfc.nasa.gov/results

This will take a while to evaluate. The "cosmological implications" manuscript alone runs to 80 page. I quickly note that they have beefed up a lot of the analysis techniques - notably, gotten rid of some kind of numerical sampling approximation that seems to have made some of the low-l amplitudes artificially high in the year-1 results. I need to go read up on some of the theory of the polarization intepretation...

antoniseb
2006-Mar-16, 07:03 PM
This will take a while to evaluate.
Agreed. No comment from me for a few days. There's lots here.

Zahl
2006-Mar-16, 08:09 PM
Fascinating stuff. The third TT peak is well defined and it is tall - ruling out MOND at high confidence. Optical depth significantly reduced and is about two sigma away from 1-year data (now 0.09, was 0.17). Reionization redshift is halved (around 10 now), ergo the population III stars should be much closer to us (reionization epoch of about 400 Myr vs. 200 Myr after the Bang). Reionization epoch does not appear to have been as long as previously believed. Scale invariance ruled out at high confidence (four sigma), the spectral index being 0.95. More later.

01101001
2006-Mar-16, 08:36 PM
For the non-wonks, the BA Blog has more accessible commentary: New WMAP results: quantum fluctuations, galaxies, and the first stars (http://www.badastronomy.com/bablog/2006/03/16/new-wmap-results-quantum-fluctuations-galaxies-and-the-first-stars/)

Edit: And, a more poetic version at: The First Star Is Born (http://www.huffingtonpost.com/phil-plait/the-first-star-is-born_b_17420.html) for the Huffington Post.

ToSeek
2006-Mar-16, 09:05 PM
Posts about the latest results moved into a separate thread.

Fraser
2006-Mar-17, 04:02 AM
SUMMARY: Scientists have gathered new evidence that supports the inflationary theory of expansion thanks new data from NASA's Wilkinson Microwave Anisotropy Probe (WMAP). The spacecraft has been making continuous observations of the cosmic background radiation; the afterglow of the Big Bang. These latest observations produced a map of the sky so detailed that scientists were able to trace how microscopic fluctuations in the primordial Universe were magnified in a trillionth of a second of rapid expansion to create the stars and galaxies we see today.

View full article (http://www.universetoday.com/am/publish/wmap_trillionth_sec.html)
What do you think about this story? post your comments below.

Zahl
2006-Mar-17, 05:03 AM
A third thread on the same subject.

Launch window
2006-Mar-17, 05:23 AM
great news !

iantresman
2006-Mar-17, 08:31 AM
SUMMARY: Scientists have gathered new evidence that supports the inflationary theory of expansion thanks new data from NASA's Wilkinson Microwave Anisotropy Probe (WMAP). The spacecraft has been making continuous observations of the cosmic background radiation; the afterglow of the Big Bang. These latest observations produced a map of the sky so detailed that scientists were able to trace how microscopic fluctuations in the primordial Universe were magnified in a trillionth of a second of rapid expansion to create the stars and galaxies we see today.

I think the article title is a bit strong, "Early Universe's Rapid Expansion Confirmed", when the text says that there is "new evidence that supports the inflationary theory of expansion". (my emphasis).

Aurora's recent post on logical fallacies (http://www.csun.edu/~dgw61315/fallacies.html) comes to mind.

Regards,
Ian Tresman

Melusine
2006-Mar-17, 01:23 PM
I think the article title is a bit strong, "Early Universe's Rapid Expansion Confirmed", when the text says that there is "new evidence that supports the inflationary theory of expansion". (my emphasis).

Aurora's recent post on logical fallacies (http://www.csun.edu/~dgw61315/fallacies.html) comes to mind.

Regards,
Ian Tresman
That's a good point. The title could have said "Early Universe's Rapid Expansion Supported." Most people think of confirm as meaning to validate a correct fact, but actually confirm is a bit weaker than asserting the truth of something:

1 : to make firm : strengthen (as a person) in resolution, conviction, loyalty, position
4 : to give new assurance of the truth or validity of : CORROBORATE (http://unabridged.merriam-webster.com/cgi-bin/unabridged?book=Third&va=corroborate) <confirm a rumor> <confirm a hypothesis or diagnosis> <confirm a plane reservation>
5 : to make firmer or more settled in a conviction, purpose, or habit <the experience confirmed him in his dislike of foreign cooking>


Anyway, it's fascinating information!

antoniseb
2006-Mar-17, 01:54 PM
I'm guessing that the detailed papers on this will be available to the general public after they get presented by the WMAP team. Someone mentioned an 80-page paper on cosmological implications (the first one I'm going to read), but I can't find a link to it yet.

Nereid
2006-Mar-17, 02:10 PM
here (http://www.bautforum.com/showthread.php?t=39381).

This story will run and run and run.

Hamlet
2006-Mar-17, 02:11 PM
I'm guessing that the detailed papers on this will be available to the general public after they get presented by the WMAP team. Someone mentioned an 80-page paper on cosmological implications (the first one I'm going to read), but I can't find a link to it yet.

Here's (http://map.gsfc.nasa.gov/m_mm/pub_papers/threeyear.html) the link to the main results page for Year 3 data. The Implications for Cosmology (http://map.gsfc.nasa.gov/m_mm/pub_papers/parameters/wmap_3yr_param.pdf) paper is among them.

Nereid
2006-Mar-17, 02:18 PM
You can get the papers here (http://map.gsfc.nasa.gov/m_mm/pub_papers/threeyear.html).

The 80-page one is Implications for Cosmology.

The Temperature Results paper (93 pages!) includes updates on the low l (2 to 10) modes that were, perhaps, the subject of the greatest number of "what's going on here?" papers. In a nutshell, the three-year results confirmed most of the year-one results, though there are some important deltas (the 'axis of evil' is still there).

I've not even downloaded the Polarisation Analysis paper yet; this is completely new material (no such data in the first year results).

Much to talk about, but I noticed that a different statistical technique was used for part of the year-three analysis, and there's a lengthy explanation of what and why (together with comparison with the year one method).

[Edit: beaten to the punch by Hamlet!]

astro-orange
2006-Mar-17, 02:56 PM
To me,the Universe looks more magical than some thirty years ago (when I started getting interested in Astronomy, "Viking"-wise). Yet, this magic is hard science, not superstition!

Nereid
2006-Mar-17, 03:22 PM
Moved to the Astronomy section.

Gerald Lukaniuk
2006-Mar-17, 06:00 PM
This makes the best sense metaphysically as it takes away a lot of the erroneous comparisions that the Big Bang was like a real earthly explosion blasting matter out in all directions. At creation before there was "space" all proto matter was probably superimposed. not compressed thus nothing could happen or "time" did not exist. Expansion of space to the full size of the universe would be instantaneous as time did not yet exist. Perhaps there is no more current expansion of space but rather red shift is due to a condensing of matter in that older larger atoms generated larger wavelenghth photons than they do now.

iantresman
2006-Mar-17, 10:21 PM
To me,the Universe looks more magical than some thirty years ago (when I started getting interested in Astronomy, "Viking"-wise). Yet, this magic is hard science, not superstition!

I agree it looks magical, but it looks like funny science to me:

The Big Bang, an action without a cause (new science, invisible, unfalsifiable)
Black holes (new science, invisible, unfalsifiable)
Dark matter (new science, invisible, unfalsifiable)
Dark energy (new science, invisible, unfalsifiable)
Neutron stars (new science, invisible, unfalsifiable)


Regards,
Ian Tresman

Nereid
2006-Mar-17, 11:04 PM
I agree it looks magical, but it looks like funny science to me:

The Big Bang, an action without a cause (new science, invisible, unfalsifiable)
Black holes (new science, invisible, unfalsifiable)
Dark matter (new science, invisible, unfalsifiable)
Dark energy (new science, invisible, unfalsifiable)
Neutron stars (new science, invisible, unfalsifiable)


Regards,
Ian TresmanFunny idea of what science is Ian. naive falisificationism - falsifiable, falsified (not even the original author - Popper - ended up supporting it) Big Bang Theory - matches observations to an astonishing extent; not even a competing theory, let alone one that also matched the obserations black holes - predicted by GR (itself tested to ~10 part per million), matches observations (SagA*, X-ray binaries, SNe, ....) DM - think, as an analogy, the neutrino, in between Pauli and Savannah River; matches observations in apparently unconnected domains to a 'shiver up your spine' level; no alternatives even worth mentioning DE - an enigma, but the WMAP results constrain its nature; combined with SNe data (which otherwise would seem to have no relevance), a consistent picture emerges, namely w = -1 {insert error bars here} neutron stars - predicted from both GR and QM (the most successful theories in physics today, QM matches lab experiments to ~12 decimal places; pulsars, magnetars, AXPs, SNe, .... all match what's expected (from the theory)) perhaps most important of all - no alternative theories can match the mainstream theories to even a trivial extent, let alone provide serious competition.That it's all somewhat unsettling may be true. But then, with the experimental resolution of the EPR paradox (Einstein lost, QM won), the universe is an exceedingly weird place, in every single atom of your body, let alone galaxies a long time ago and far, far away.

[Moderator note: if any reader wishes to ask about any of the items in these two lists, please start a thread in BAUT's Q&A section.]

Melusine
2006-Mar-18, 12:12 AM
here (http://www.bautforum.com/showthread.php?t=39381).

This story will run and run and run.
This is an example of why I don't think we need any more sections on BAUT (except, perhaps for games). We're told to comment here, then you say to go talk about it there....I didn't get a chance to look at the Astronomy section today yet. Now you're saying to ask questions about your lists in the Q&A section. :hand:

I just want Fraser to know his articles are being read. :)

antoniseb
2006-Mar-18, 12:45 AM
Now you're saying to ask questions about your lists in the Q&A section.

I believe that nereid is asking people to discuss Ian's provocative statements about black holes, neutron stars, and dark matter in the Q&A section. This thread is about the WMAP Second Release discussion.

antoniseb
2006-Mar-18, 12:39 PM
I've read the implications for Cosmology paper, but I think I have to read it again. There are a few terms that I am unfamiliar with. I'll be asking for some help on a few of them.

czeslaw
2006-Mar-18, 02:12 PM
This WMAP result may suggests:
A. There was a mysterious rapid inflation in the begining of Big Bang.
B. There was a concentration of the energy in a certain volume and immediatelly transformation of this energy into a matter/antimatter - the Begining was due to the concentrated energy in non zero volume .
This "B" solution seems more realistic.

Zahl
2006-Mar-18, 09:58 PM
Ok, I've read most of the papers and it's time for some more comments. When combined with other recent data sets (CBI, VSA, BOOM, 2df, SDSS, etc.), the parameter constraints are INSANE. See

http://lambda.gsfc.nasa.gov/product/map/current/params/lcdm_all.cfm

and download the Postscript Parameter Table and look at the errors. Eg.

Spectral index n_s = 0.938 +0.013/-0.018 (n_s < 1 means that there is less power on small scales)
Optical depth tau = 0.069 +0.026/-0.029
Hubble parameter H0 = 71 km/s/Mpc +1/-2
Redshift of reionization Zr = 9.3 +2.8/-2.0

Unbelievable precision! And the spectral index from the combined data set is almost _five sigma_ away from unity at 0.938! This relatively large and statistically significant deviation from scale invariance is not only good news for simple inflation models because their prediction got verified, but it also means that gravitational waves should have a high amplitude that is just somewhat below our current detection threshold. Of course the claim that inflation was 'confirmed' with WMAP3 is not true and there were valid models (so called hybrid models) that predicted a spectral index that was greater than unity, but these models are more complicated and appear to be ruled out now. The stage is set for GW detection.

I am dissappointed that they made no attempt to explain or even quantify the 'axis of evil'. They merely briefly summarized the various 'claims' of the past few years and stated that most of them are probably still there because WMAP3 data is consistent with WMAP1.

I'm also somewhat disappointed that the best LCDM fit has a relatively modest probability of 13.9% based on 1468 chi squared for 1410 degrees of freedom. It is a reasonable fit and better than WMAP1 (that had a probability of 4.5%), but not something I would call 'excellent'. They had three years to work on it, but the TT curve still shows some nasty spikes before and around the first peak. Higher moments have seen a significant reduction in the spikes, but interestingly lower moments have not (see fig. 17 & fig. 20 in Hinshaw et al.). Is this a sign of oscillatory microstructure or something else? They test a couple such models, but get no major reduction in chi squared for the additional degrees of freedom.

I'm also disappointed that they didn't include the most recent CBI data from last September in their analysis (CBI from 2004 and Boomerang data from last July is included).

GBendt
2006-Mar-18, 11:40 PM
Hi,

The polarization found in the microwave background radiation is not necessarily caused by the inflation process which is thought to have taken place, as was proposed recently, some 13,7 billion years ago. There are many processes taking place in space which are able to polarize microwave radiation. I am afraid that the idea to use this polarization as a proof of an inflation process that took place at the beginning of the universe may end as a kind of wishful thinking.

We have just even started to look at the skys with our new powerful infrared, microwave, UV, X-ray and gamma satellites, and we should consider the findings of all these satellites from all over the heavens, and then lean back and evaluate them.

We have to deal with 140 billion galaxies, and vast spaces between them, filled with void, with hot intergalactic gas, with dust particles, powerful magnetic fields, fast electrons and protons, and radiation. There is a lot to watch and observe, just to gather the pieces of information which may finally give a comprehensive picture.

Let me put it this way: I think that the universe was not designed to be understood simply by the brightness of skilful human beings. The complexity may by far exceed any contemporary theory.
Theories may be brilliant, reasonable and beautyful. But that does not mean anything. We can only know whether the theories are right or wrong if we know all the facts, and we are still quite far from that. And thanks to the cuts in science projects, this is not very much likely to change...

Regards,

Günther

gzhpcu
2006-Mar-19, 06:46 PM
http://www.space.com/scienceastronomy/060316_wmap_results.html

More support for the BB as well...

antoniseb
2006-Mar-19, 06:51 PM
I'm not sure this belongs in ATM.

Wolverine
2006-Mar-20, 12:30 AM
We have existing threads on the subject here (http://www.bautforum.com/showthread.php?t=39398) and here (http://www.bautforum.com/showthread.php?t=39381).

Moved from ATM to Astronomy.

Locked.

bigsplit
2006-Mar-20, 05:51 PM
At creation before there was "space" all proto matter was probably superimposed. not compressed thus nothing could happen or "time" did not exist. Expansion of space to the full size of the universe would be instantaneous as time did not yet exist. .

This is a great point. The astronomical expansion occuring so rapidly could be misleading. If the expansion was at c or less, with "billions" of years before time became measurable, would we witness the same result. That time stuff is tricky.

Grand_Lunar
2006-Mar-20, 10:55 PM
Neutron stars (new science, invisible, unfalsifiable)

Um...neutron stars ARE visible. We can see the one inside the crab nebula (actually a pulsar, but you get the idea.




perhaps most important of all - no alternative theories can match the mainstream theories to even a trivial extent, let alone provide serious competition.

Not even this one?
http://www.bautforum.com/showthread.php?t=33579

Just asking, trying to confirm my belief of that issue.

Gerald Lukaniuk
2006-Mar-21, 05:32 PM
These people are patting themselves on the back over an extremely precise. myopic and otherwise useless study leading to a conclusion in their own words:
"Cosmology requires new physics beyond the standard model of particle physics: dark
matter, dark energy and a mechanism to generate primordial fluctuations."

VanderL
2006-Mar-21, 10:29 PM
Ok, I've read most of the papers and it's time for some more comments. When combined with other recent data sets (CBI, VSA, BOOM, 2df, SDSS, etc.), the parameter constraints are INSANE. See

http://lambda.gsfc.nasa.gov/product/map/current/params/lcdm_all.cfm

and download the Postscript Parameter Table and look at the errors. Eg.

Spectral index n_s = 0.938 +0.013/-0.018 (n_s < 1 means that there is less power on small scales)
Optical depth tau = 0.069 +0.026/-0.029
Hubble parameter H0 = 71 km/s/Mpc +1/-2
Redshift of reionization Zr = 9.3 +2.8/-2.0

Unbelievable precision! And the spectral index from the combined data set is almost _five sigma_ away from unity at 0.938! This relatively large and statistically significant deviation from scale invariance is not only good news for simple inflation models because their prediction got verified, but it also means that gravitational waves should have a high amplitude that is just somewhat below our current detection threshold. Of course the claim that inflation was 'confirmed' with WMAP3 is not true and there were valid models (so called hybrid models) that predicted a spectral index that was greater than unity, but these models are more complicated and appear to be ruled out now. The stage is set for GW detection.

I am dissappointed that they made no attempt to explain or even quantify the 'axis of evil'. They merely briefly summarized the various 'claims' of the past few years and stated that most of them are probably still there because WMAP3 data is consistent with WMAP1.

I'm also somewhat disappointed that the best LCDM fit has a relatively modest probability of 13.9% based on 1468 chi squared for 1410 degrees of freedom. It is a reasonable fit and better than WMAP1 (that had a probability of 4.5%), but not something I would call 'excellent'. They had three years to work on it, but the TT curve still shows some nasty spikes before and around the first peak. Higher moments have seen a significant reduction in the spikes, but interestingly lower moments have not (see fig. 17 & fig. 20 in Hinshaw et al.). Is this a sign of oscillatory microstructure or something else? They test a couple such models, but get no major reduction in chi squared for the additional degrees of freedom.

I'm also disappointed that they didn't include the most recent CBI data from last September in their analysis (CBI from 2004 and Boomerang data from last July is included).


Thanks Zahl for this excellent summary. The question of the "axis of evil" will need to be addressed (and someone will probably soon post an ArXive paper) and the best LDCM fit was 13.9%? Hmm, what will be needed to improve this (if it can be done at all)? New instruments, different models?

Cheers.

Zahl
2006-Mar-22, 01:55 PM
the best LDCM fit was 13.9%? Hmm, what will be needed to improve this (if it can be done at all)? New instruments, different models?

Well, it would be quite preposterous to assume that the structure of the universe could be fully described with only six parameters (the LCDM parameters). Thus it is likely that additional parameters (such as parameter omega_k describing a non-flat universe or parameter dn_s/d ln{k} describing a running spectral index, that is the spectral index varies as a function of scale) are needed at some point, but the data does not yet justify their inclusion. Adding them now improves the fit, but not to a compelling degree. Interestingly, a non-zero running spectral index would be bad news for (simple) inflation models.

The quadrupole/octopole anomalies (the axis of evil) does not noticeably degrade the fit since the two multipoles are drops in the ocean.

Modelling the pre-peak glitches somehow could have a huge effect on the goodness of fit, because much of the excess chi squared comes from them.

A better galactic foreground treatment would undoubtedly improve the fit, because some residuals still contaminate the signal. Unfortunately we can't measure the CMB in intergalactic space...

Some secondary effects (such as CMB lensing) that are not yet included in the analysis could also affect the goodness of fit.

Even better understanding of the instrumental systematics could also improve the goodness of fit, but probably not significantly, because the instrument is now very well understood.

So it is very likely that the fit can be improved further.

czeslaw
2006-Mar-22, 04:48 PM
Well, it would be quite preposterous to assume that the structure of the universe could be fully described with only six parameters (the LCDM parameters). Thus it is likely that additional parameters (such as parameter omega_k describing a non-flat universe or parameter dn_s/d ln{k} describing a running spectral index, that is the spectral index varies as a function of scale) are needed at some point, but the data does not yet justify their inclusion. Adding them now improves the fit, but not to a compelling degree. Interestingly, a non-zero running spectral index would be bad news for (simple) inflation models.
So it is very likely that the fit can be improved further.
I know that traditional BBT start from a zero volume and then was a space inflation, but does the WMAP observation show the overluminal velocity (how fast ?) or it shows just a certain volume when the normal expansion began ?
Czeslaw

Duane
2006-Mar-22, 05:35 PM
I have merged three separate threads on this subject togeather.

Cougar
2006-Mar-23, 03:11 PM
...myopic and otherwise useless study....
Myopic? Nearsighted? Ha ha! You could not have chosen a more inappropriate and inaccurate word under the circumstances! Useless? A comment not even worthy of a response.

Zahl
2006-Mar-23, 06:04 PM
does the WMAP observation show the overluminal velocity (how fast ?) or it shows just a certain volume when the normal expansion began ?
Czeslaw

Pretty fast considering that inflation supposedly increased the scale factor by a factor of 10^30 in 10^-34 seconds or so. WMAP does not shows us inflation "in action" because the CMB is a snapshot of sorts that captured the state of the universe as it was about 380000 years after inflation ended. However, if inflation really happened, then the CMB has distinctive fingerprints imprinted on it by inflation. Some of them have already been detected and measured as predicted (and explained earlier in this thread and elsewhere), but the "smoking gun" evidence, B-mode polarization from gravity waves, has not yet been found. The "volume shown by WMAP" is consistent with infinite volume when "the normal expansion" began.

czeslaw
2006-Mar-23, 08:46 PM
Pretty fast considering that inflation supposedly increased the scale factor by a factor of 10^30 in 10^-34 seconds or so. WMAP does not shows us inflation "in action" because the CMB is a snapshot of sorts that captured the state of the universe as it was about 380000 years after inflation ended. However, if inflation really happened, then the CMB has distinctive fingerprints imprinted on it by inflation. Some of them have already been detected and measured as predicted (and explained earlier in this thread and elsewhere), but the "smoking gun" evidence, B-mode polarization from gravity waves, has not yet been found. The "volume shown by WMAP" is consistent with infinite volume when "the normal expansion" began.
Thank you Zahl for explanation.
I was asking for it, because the scale factor 10^30 means almost an immediatelly creation of a certain space.

If there was a certain space volume just at the very begining - our observable Universe began perhaps of this certain volume. In this volume was the initiating energy gathered and transformed into a matter and Big Bang started.

We need the inflation to escape from a superdense singularity but if the gathered matter was like a Gravastar with Dark Energy (-)pressure ?
Regards
Czeslaw

Nereid
2006-Mar-24, 01:24 AM
To what extent are the low-l modes not strongly constrained by (any) theory, in the sense that we have only one universe?

The WMAP papers also have some interesting (non-cosmological) observations - the SZE, the point sources, and the spectrum of the various foregrounds.

The low-l observations will be intensely scrutinised, analysed, and dozens (more) papers written about them.

I wonder to what extent these results will lead to modifications of the Planck mission?

antoniseb
2006-Mar-24, 01:38 AM
I wonder to what extent these results will lead to modifications of the Planck mission?

If I had to guess, I'd say that the instruments and observing plan for Planck is written in stone, but these results may lead to some updates in the analysis.

GOURDHEAD
2006-Mar-24, 02:17 PM
For those of us terminology challenged, could someone review (or provide links to) definitions for terms unique to CMB data analysis including B-mode data and the specifics of the quadrupole and octopole configurations.


We need the inflation to escape from a superdense singularity but if the gathered matter was like a Gravastar with Dark Energy (-)pressure ?
After the volume increased to a sphere of one light year radius (or one meter as you prefer) one could be forgiven for describing the universe as superdense if it contained all the mass that has been observed in the currently observable universe.

Am I the only one incapable of resolving why light from each point in the universe has not caught up with every other point since inflation ended thus making the entire universe observable from every point within it assuming we had adequate instruments. Inflation ended prior to one second after the BB, and, if we assume one light year radius for the univerase at that time and that the universe continues to expand at less than light speed, the maximum separation for points within the universe would then have been two light years. How long would it take for light from each of these points to reach objects located at the other assuming reasonable values for the Hubble parameter with reasonable constraints on its variability? How would reasonableness be determined?

folkhemmet
2006-Mar-25, 02:15 AM
Congrajulations to the WMAP team on the release of the 3-year data!

From what I can tell, the supberbly accurate 3-year results are a product of an exhaustive and painstakingly detailed search for systematic errors and foreground contamination. A number of new techniques were employed to see if the data is of high enough quality to be used for a cosmological analysis. So, the combination of longer integration time and a more thorough analysis assures us the results are giving us a solid picture/understanding of cosmic evolution. I certainly don't think cosmology is solved, as there are still mysteries and things that need to be explained, but at least we now a rough outline of cosmic evolution. Think about it like this: we knew the size and shape of the earth before we knew what it was made out of; similarly, we now know the size, expansion rate, and shape (i.e, flatness) of the universe even though we do not yet know what is the dark energy and the dark matter. Humanity has little to be proud of these days on Earth. Nevertheless, we should be proud of the fact that we come as far as we have in recent years in terms of being able to read the "universe story" in the sky.

Zahl
2006-Mar-28, 09:00 AM
To what extent are the low-l modes not strongly constrained by (any) theory, in the sense that we have only one universe?

Hiranya Peiris answered a similar question over at cosmicvariance.com:

"Cosmic variance goes as sqrt(2/(2l+1)) * C_l^{theory}. This means that the CV error at l=200 is bigger than at l=100 because the C_200/C_100 ratio wins over the factor of ~2 increase in the number of measurable modes."

NubiWan
2006-Mar-28, 07:53 PM
"..,the erroneous comparisions that the Big Bang was like a real earthly explosion blasting matter out in all directions."

With an expansion rate "from subsubmicroscopic to astronomical" in a "trillionth of a second," makes the distinction kind of blurry to me just watching from the side lines. But WOW, what a fantasic universe science reveals, far from being devoid of awe and wonder for me. Could someone who understands the above statement, walk me through the 'how come' using small words and a minimum of math? Don't suppose the fuse or trigger, is uncovered by the latest data, huh?

Much thanks in advance. :)

Cougar
2006-Mar-28, 08:20 PM
"..,the erroneous comparisions that the Big Bang was like a real earthly explosion blasting matter out in all directions."... Could someone who understands the above statement, walk me through the 'how come' using small words and a minimum of math?
Well, an earthly explosion sends matter out into existing space. With the big bang, there was no existing space to explode into. The BB "explosion" blasted space out in all directions, and the matter essentially went along for the ride.


Don't suppose the fuse or trigger, is uncovered by the latest data, huh?
I haven't read all the papers, but no, this would have been in the headlines if it was included in the latest release.

ToSeek
2006-Mar-29, 02:35 PM
A couple of blog entries worth perusing:

WMAP for Dummies (http://catdynamics.blogspot.com/2006/03/wmap-for-dummies.html)

WMAP: Polarization in the Low-Signal Regime (http://blog.lib.umn.edu/mill1974/EGAD/041694.html)

nodem
2006-Mar-29, 05:21 PM
For those in the area (Cambridge, MA), you may be interested in this seminar for the Harvard-Smithsonian Center for Astrophysics Institute for Theory and Computation:

Thursday, March 30th
11:00 Phillips Auditorium
Harvard-Smithsonian Center for Astrophysics
60 Garden St.

David Spergel (Princeton)
New Results from WMAP

http://cfa-www.harvard.edu/itc/events/

antoniseb
2006-Mar-29, 06:49 PM
Thanks, I'll try and get time off to get there... I seem to recall parking being an issue.

Wolverine
2006-Mar-30, 12:19 AM
FWIW: I caught this press release (http://www.eurekalert.org/pub_releases/2006-03/cuns-sdr032906.php) earlier today.

VanderL
2006-May-08, 09:55 AM
Any comments on this finding?
http://xxx.lanl.gov/abs/astro-ph/0605135

Cheers.

antoniseb
2006-May-08, 11:48 AM
Any comments on this finding?


I expect there will be something interesting there when we sort it all out. Thankfully the important calculations from the WMAP data have little to do with quadrapole and octopole intensities.

VanderL
2006-May-08, 04:37 PM
I expect there will be something interesting there when we sort it all out. Thankfully the important calculations from the WMAP data have little to do with quadrapole and octopole intensities.

I think you misunderstand the implications; apart from the as yet unidentified foreground "contamination", the paper explains that inflationary models are in trouble and the results as presented by the WMAP team, use corrections that produce results that are not observed but rely on unproven assumptions:


Another striking fact seen in Table VII is that the quadrupole and octopole of cut-sky maps, as well as S 1, 2 statistics, are significantly lower than in the full-sky ILC maps, both for year 1 and year 123. This seems
to be because of a combination of effects — the "galactic bias correction" and the time-dependent radiometer gain model certainly, but perhaps also just the minimal variance procedure used to build the ILC. This reflects the fact that the synthesized full sky maps show correlations at large angles that are simply not found in the underlying band maps. This does not seem reasonable to us — that one starts with data that has very low correlations at large angles, synthesizes that data, corrects for systematics and foregrounds and then concludes that the underlying cosmological data is much more correlated than the observations — in other words that there is a
conspiracy of systematics and foreground to cancel the true cosmological correlations.

Cheers.

Doodler
2006-May-08, 06:00 PM
Would it be possible to explain the initial expansion of the universe to several hundred thousand lightyears in size in a trillionth of a second or so not so much as expansion from singularity, but as the "contact area" of the colliding branes expressed in four dimensional space-time?

Zahl
2006-May-11, 12:27 PM
Any comments on this finding?
http://xxx.lanl.gov/abs/astro-ph/0605135

Cheers.

This reinforces the notion that the large scale fluctuations are a mess and in serious conflict with the LCDM predictions. Before anyone gets rogue ideas I hasten to add that this is not a significant problem for the standard big bang cosmology as a whole. The anomalous multipole moments are a drop in the ocean in the big picture.

But the arguments (purely statistical BTW) are problematic for inflation. The WMAP team did not address the two point correlation function in the 3-year papers at all, but the authors of the present paper find it violates the inflationary LCDM predictions at 99.97% level (this deals with only the large scale fluctuations at 60+ degrees and the galaxy cut is imposed). When they assess this in conjunction with other independent anomalies, they find that the probability for these results occurring by chance alone is 1:100 million (!). They also argue that the WMAP team's decision to use Maximum Likelihood Estimation for multipoles 2-10 (that brought them in better agreement with theory) was in error, because MLE analysis is valid only if the sky and noise are isotropic and there is significant evidence that this is not the case.

Different statistical methods give different results and different authors choose to include different anomalies in their analysis. The probabilities are also affected by how rigorously one tries to avoid a posteriori odds (cherry picking anomalous features and ignoring expected features). Thus the WMAP team reluctantly quoted a probability of "less than 2%" for the apparent non-gaussianity in their conservative and limited analysis and didn't think much of it. This is somewhat biased on their part as the apparent deviation from scale invariance, a major finding in the 3-year data that was widely publicized, was hailed as a confirmation of an important prediction of simple inflation models. Yet it is of precisely same confidence level than and in conflict with the 98%+ evidence for non-gaussianity that the WMAP team reported.

VanderL
2006-May-14, 09:30 AM
This reinforces the notion that the large scale fluctuations are a mess and in serious conflict with the LCDM predictions. Before anyone gets rogue ideas I hasten to add that this is not a significant problem for the standard big bang cosmology as a whole. The anomalous multipole moments are a drop in the ocean in the big picture.

But the arguments (purely statistical BTW) are problematic for inflation. The WMAP team did not address the two point correlation function in the 3-year papers at all, but the authors of the present paper find it violates the inflationary LCDM predictions at 99.97% level (this deals with only the large scale fluctuations at 60+ degrees and the galaxy cut is imposed). When they assess this in conjunction with other independent anomalies, they find that the probability for these results occurring by chance alone is 1:100 million (!). They also argue that the WMAP team's decision to use Maximum Likelihood Estimation for multipoles 2-10 (that brought them in better agreement with theory) was in error, because MLE analysis is valid only if the sky and noise are isotropic and there is significant evidence that this is not the case.

Different statistical methods give different results and different authors choose to include different anomalies in their analysis. The probabilities are also affected by how rigorously one tries to avoid a posteriori odds (cherry picking anomalous features and ignoring expected features). Thus the WMAP team reluctantly quoted a probability of "less than 2%" for the apparent non-gaussianity in their conservative and limited analysis and didn't think much of it. This is somewhat biased on their part as the apparent deviation from scale invariance, a major finding in the 3-year data that was widely publicized, was hailed as a confirmation of an important prediction of simple inflation models. Yet it is of precisely same confidence level than and in conflict with the 98%+ evidence for non-gaussianity that the WMAP team reported.


Oops, nearly missed your post Zahl, thanks for explaining the details, I'm still stuck on one point though, how are these anomalies "a drop in the ocean"? Is BB cosmology such an imprecise collection of theories that it can incorporate any contrary evidence? If the scenario of inflation is incorrect, aren't we back at the point where it was first proposed?

Cheers.

trinitree88
2006-May-14, 11:40 AM
Oops, nearly missed your post Zahl, thanks for explaining the details, I'm still stuck on one point though, how are these anomalies "a drop in the ocean"? Is BB cosmology such an imprecise collection of theories that it can incorporate any contrary evidence? If the scenario of inflation is incorrect, aren't we back at the point where it was first proposed?

Cheers.

VanderL. Perhaps the universe is capable of precognition. Then when it expanded superluminally, it "knew" a priori, where the Milky Way galaxy would form, and in what orientation the plane of the solar system would be in ~ 2003. (BTW..That's a little further into the future than most psychics will go..)
That way, when scientists launched the WMAP satellite,and collected it's data, the alignment of the anisotropy of the radiation field with the solar system's axis could be forseen without statistics intruding without a one in a hundred million unlikeliness. Then inflationary models would be fine. Otherwise, that's a mighty big pothole to negotiate in the road of reasonableness of conclusions. It will be interesting to see how it gets patched up.
Zahl's comment on their use of a statistical analysis that requires as condition isotropy of the noise, yet was published anyway....does not bode well for truth-in-peer review, editorial responsibility, or the advancement of science. It unfortunately reminds me of the suppression of the statistical analyses of quasar/galaxy alignments...H.Arp, Max Planck Inst. It is a sad day indeed for science.:think:

Zahl
2006-May-15, 09:43 AM
Is BB cosmology such an imprecise collection of theories that it can incorporate any contrary evidence?

No, but inflation comes pretty close. It could have dealt with any value for the spectral index (eg. 0.85, 0.9, 0.95, 1, 1.05, 1.1, 1.15) that WMAP might have discovered for the CMB. While specific inflation models can and do give specific predictions, there are three main branches of inflation models (small field, large field and hybrid) and a huge number of specific models in each branch, but no way to theoretically rule out the wrong ones. Together these models saturate the entire parameter space. The same thing for gravity wave amplitude - if some precision measurement finds no GW signal, a signal that is x times weaker would still be compatible with a huge number of inflation models. And if omega had not been 1, inflation would still have been compatible with open universes. It is the same thing for many other parameters too - there are enough theoretically valid models to saturate the entire parameter space and few if any measurements can be done to conclusively rule out all inflation models.

VanderL
2006-May-16, 08:18 PM
No, but inflation comes pretty close. It could have dealt with any value for the spectral index (eg. 0.85, 0.9, 0.95, 1, 1.05, 1.1, 1.15) that WMAP might have discovered for the CMB. While specific inflation models can and do give specific predictions, there are three main branches of inflation models (small field, large field and hybrid) and a huge number of specific models in each branch, but no way to theoretically rule out the wrong ones. Together these models saturate the entire parameter space. The same thing for gravity wave amplitude - if some precision measurement finds no GW signal, a signal that is x times weaker would still be compatible with a huge number of inflation models. And if omega had not been 1, inflation would still have been compatible with open universes. It is the same thing for many other parameters too - there are enough theoretically valid models to saturate the entire parameter space and few if any measurements can be done to conclusively rule out all inflation models.

Thanks Zahl,

This way we could "constrain" the models endlessly without getting anywhere. I wouldn't call it science if there is no way of devising any definite tests. It's probably a good field to work in, as long as you can convince your sponsors it is important research. Until of course someone shows the Universe isn't expanding :D

Cheers.

Jerry
2006-May-30, 03:06 PM
Funny idea of what science is Ian... perhaps most important of all - no alternative theories can match the mainstream theories to even a trivial extent, let alone provide serious competition...

Think about what you are saying here Neried: It does not matter how many times an experiment is repeated, if the same lack of control over parameters is repeated as well, the conclusion can still be wrong.

In the mainstream study of the cosmos, parameters are not being controlled, they are being multiplied. Any argument that this represents progress must be tempered by the realization that the complexity of the machine does not directly correlate with the reliability of the product.

folkhemmet
2006-May-30, 08:37 PM
”Think about what you are saying here Neried: It does not matter how many times an experiment is repeated, if the same lack of control over parameters is repeated as well, the conclusion can still be wrong.

In the mainstream study of the cosmos, parameters are not being controlled, they are being multiplied. Any argument that this represents progress must be tempered by the realization that the complexity of the machine does not directly correlate with the reliability of the product.”
__________________

This gets back to my point that those who incessantly complain that the 6 parameter model of cosmology is complex and unaesthetic. My interpretation of Jerry’s analogy between the mainstream study of the cosmos and the complexity of a machine is that he thinks that the current cosmological model is epicyclical and complex, and cosmologists keep “multiplying” the parameters instead of critically evaluating basic assumptions.

Ironically, however, many of those who complain about the complexity of the cosmological model with its “multiplying” parameters are those, like Jerry, who say that mainstream cosmology is failing to recognize the complexity of the Universe. So, on the one hand you have the anti-cosmologist/radical skeptics complaining that there are too many parameters in mainstream cosmology. On other hand, you have him or her saying that the Universe is much more complex than we can imagine. This is pretty convoluted reasoning; obviously reveals more about those using it than it does about the Universe. When an observation comes out implying that we understand something about the universe, they play the Universe is more complex card. When an observation comes out implying that the Universe is more complex, they play the Universe is simpler card. Call it Big-Bang or something else, as it not so much the individual theories that bother them. What bothers them is the idea that we are actually getting somewhere in terms of understanding the story of the stars, galaxies, and Universe—the greatest story ever. Moreover, those who complain about the complexity of the current cosmological model also often fail to mention that there are other cosmological models which have many more parameters.

I do however agree with Jerry’s point in his first paragraph. Jerry’s first paragraph seems to apply to the DAMA dark matter results. DAMA upgraded their experimental apparatus in 2003. This upgrade seems like just a larger version of their previous experiment which gave positive results for a DM signal in the late 1990s. Since DAMA announced that signal, a number of others groups appear to have probably refuted it. So, I agree, people should think long and hard about their basic assumptions: applying them on a larger scale is unlikely to convince others who were skeptical of them in the first place. This healthy criticism is different from the kind of skepticism found in many anti-Big Bang circles, however. These people are eternal skeptics; they believe that everything is subject to doubt. Sure, I’ll grant them that everything is subject to doubt: this means, however, based on their own logic, that the notion that everything is subject to doubt is itself subject to doubt! It is easy to be skeptical of everything.

Jerry
2006-May-31, 04:04 PM
I have to agree with you, Folkhemmet, that blind skepticism can be as unhealthy as blind faith. I like to think that my critic of WMAP data analysis is thoughtful and educated, and not just paper bashing. Let me tell you why:
I develop deconvolution and data reductions schemes for X-ray, ultrasonic and impedance based analytical systems. When I first saw COBE microwave results, I was intrigued by the way they subtracted out the galactic contamination. In my study of the guts of the COBE papers, I was looking for techniques that could be used to remove artifacts from similar data. These techniques make assumptions about the power functionality of the interfering sources within our own galaxy. I was disappointed to discover the techniques were quite useless in the world I work in; because I cannot make the assumption that I understand the nature of every possible contaminate. (If a specific contaminate is known or suspected to be harbored, yes these methods could work.)
This problem is inherent in any and all interpretations of COBE and WMAP data: An assumption is made about the magnitude of local galactic interference, and this power spectrum assumption is also essential in estimating the nature of the microwave interference caused by all the known and unknown clusters of galaxies between here and ‘the beginning’ of the universe as we know it.
WMAP researchers must make the assumption about the power function of the local microwave structure, and there is no way to test this assumption. However, certain sanity checks can be applied to the results: 1) Does the spectrum match prior expectations. 2) Is there any evidence of residual contamination? WMAP fails both of these tests: The secondary peaks are much weaker than expected, and so is the polarization. Also, the bias, the axis of symmetry in the Zodiac plane is both unexpected and unexplained.
Since this bias exists with a high level of confidence, it can also be stated with a high level of confidence that the WMAP spectrum contains unknown and uncharacterized contaminants: It is like trying to separate an ancient road from a modern one: If there are oil drippings along the road, somebody at sometime has used it for a jeep trail. The ancients may or may not have used the same path, but without pot shards or other discriminating evidence, it is just a guess. We really do not have a method for separating an ancient microwave signal from a local one, and since the reason behind the axis of symmetry is unknown, unquantified and unseperatable from ancient sources, only very limited confidence should be placed in these analysis. I am a little surprised WMAP principles have not attached these critical caveats to their conclusions.

turbo-1
2006-Jun-01, 01:40 AM
Thanks Zahl,

This way we could "constrain" the models endlessly without getting anywhere. I wouldn't call it science if there is no way of devising any definite tests. It's probably a good field to work in, as long as you can convince your sponsors it is important research. Until of course someone shows the Universe isn't expanding :D

Cheers.Well, there's a little glitch with the expanding universe idea. This idea arose from redshift data, after it was recognized that the light from galaxies farther away was redshifted more and more as a general rule. Interestingly, every engineer knows that there is no such thing as lossless transmission of energy, yet mainstream cosmologists assume that light can propagate through light-years of "empty" space with no loss of energy. This is not how our world works on a fundamental level, so why should "empty" space get a different set of rules? We know that space is not empty, but is populated with a sea of virtual particles - the idea that the speed of light in space is constant and that the texture and optical properties of space is constant from place to place is the real problem.

antoniseb
2006-Jun-01, 12:23 PM
...every engineer knows that there is no such thing as lossless transmission of energy, yet mainstream cosmologists assume that light can propagate through light-years of "empty" space with no loss of energy...

Turbo-1, this is a thread about the WMAP results. Jerry Jensen and VanderL are ATM posters just as you are, but they at least were looking at the WMAP results. Your post here is a hijack of the topic. This is an official warning to not hijack threads.

Nereid
2006-Jun-01, 03:22 PM
I have to agree with you, Folkhemmet, that blind skepticism can be as unhealthy as blind faith. I like to think that my critic of WMAP data analysis is thoughtful and educated, and not just paper bashing. Let me tell you why:
I develop deconvolution and data reductions schemes for X-ray, ultrasonic and impedance based analytical systems. When I first saw COBE microwave results, I was intrigued by the way they subtracted out the galactic contamination. In my study of the guts of the COBE papers, I was looking for techniques that could be used to remove artifacts from similar data. These techniques make assumptions about the power functionality of the interfering sources within our own galaxy. I was disappointed to discover the techniques were quite useless in the world I work in; because I cannot make the assumption that I understand the nature of every possible contaminate. (If a specific contaminate is known or suspected to be harbored, yes these methods could work.)
This problem is inherent in any and all interpretations of COBE and WMAP data: An assumption is made about the magnitude of local galactic interference, and this power spectrum assumption is also essential in estimating the nature of the microwave interference caused by all the known and unknown clusters of galaxies between here and ‘the beginning’ of the universe as we know it.
WMAP researchers must make the assumption about the power function of the local microwave structure, and there is no way to test this assumption. However, certain sanity checks can be applied to the results: 1) Does the spectrum match prior expectations. 2) Is there any evidence of residual contamination? WMAP fails both of these tests: The secondary peaks are much weaker than expected, and so is the polarization. Also, the bias, the axis of symmetry in the Zodiac plane is both unexpected and unexplained.
Since this bias exists with a high level of confidence, it can also be stated with a high level of confidence that the WMAP spectrum contains unknown and uncharacterized contaminants: It is like trying to separate an ancient road from a modern one: If there are oil drippings along the road, somebody at sometime has used it for a jeep trail. The ancients may or may not have used the same path, but without pot shards or other discriminating evidence, it is just a guess. We really do not have a method for separating an ancient microwave signal from a local one, and since the reason behind the axis of symmetry is unknown, unquantified and unseperatable from ancient sources, only very limited confidence should be placed in these analysis. I am a little surprised WMAP principles have not attached these critical caveats to their conclusions.Perhaps I have missed something ... didn't both COBE and WMAP make available pretty much the full set of data collected, both 'raw' and 'processed'? Aren't there at least a dozen (http://background.uchicago.edu/~whu/cmbex.html) other (smaller angular scale) high quality observations of the CMB, using a variety of techniques and analyses? Doesn't anyone, including Jerry Jensen, have the opportunity to perform their own analyses of the raw data? to write papers critiquing the data collection methods, the data analysis methods, etc? Doesn't the WMAP team go to considerable lengths to consider possible sources of contamination, of degeneracy in the results, of bias, of ...?

Don't get me wrong; it could well turn out that there is some subtle (or not so subtle) flaw in WMAP, in the analyses; that there are confounding factors which render all x dozen CMB studies' results meaningless (despite their being designed, installed, conducted, analysed, etc independently), and so on.

But this possibility exists for everything we do in science, observational cosmology (and the CMB) is not any different.

And imagine how well-known you'd become if you were the person who first did the study to convincingly show the flaws (or, better, show that it can all fit with some alternative idea, much much better)!

How about we have a specific critique of the mission, the data collection, the data pipeline, the CMB extraction approaches and techniques, instead of unfocussed skepticism.

For example
An assumption is made about the magnitude of local galactic interference, and this power spectrum assumption is also essential in estimating the nature of the microwave interference caused by all the known and unknown clusters of galaxies between here and ‘the beginning’ of the universe as we know it.What assumptions? What did the WMAP team do to test the validity of those assumptions? To what extent did the COBE team use the same assumptions? To what extent does the quite different design of the two instruments (and the analyses) address these assumptions?

On the more general topic (the extent to which there are viable alternative cosmologies), I have started a thread which invites just such discussion (http://www.bautforum.com/showthread.php?t=42172).

folkhemmet
2006-Jun-01, 05:03 PM
Thanks for the reply Jerry. My position is that there are scientific facts about the structure and evolution of the universe which are well-established, but the quest for a complete understanding of the cosmos will probably never cease. Those who say WMAP has solved cosmology (there are people who believe this) are almost surely wrong. I call this group the "extreme optimists." But I disagree, however, with the other extreme: those who belong to the cosmological version of the Flat Earth Society who tend to go by the maxim: "everybody else is wrong, and I am right, and any test which refutes my idea must be wrong, and if I am not right then perhaps the whole endeavor of trying to understand the cosmos is hopeless." I call this group the extreme pessimists. Ironically, these two groups may have more in common with each other than either would like to admit.

The extreme pessimist group's way of thinking is completely analogous to the child who says "if I cannot have my ice-cream cone then nobody can", and then the child throws the ice-cream cone in the trash, or, the man or woman who says "if I cannot have my boyfriend or girlfriend then nobody can."


Turbo-1, of course, all of the WMAP scientists and most other cosmologists who believe that there are some things we know about the structure and evolution of our Universe are all just a bunch of sheep flocking uncritically to the standard model. All of the scientific tests of this idea are flawed, and there is massive conspiracy afoot to suppress viable alternative ideas. Never is there mention by these extreme pessimists how famous an astronomer would be if he or she found incontrovertible proof that the Big Bang idea is basically incorrect. Also, those who are trying to come up with major departures from Big Bang theory almost always have to go to huge extremes outside of what has been proven as factual to construct their models. These people are the cosmological version of the Flat Earth Society. But again, it’s all just a big conspiracy and everybody else who uses the scientific method and has spent lots of time and effort testing and thinking about these ideas is automatically wrong.

In the end, I believe it comes down to whether you think the WMAP team is part of the extreme optimist group or the extreme pessimist group. Given their exquisitely careful and thorough analysis of the data and more years of experience working in science than years I've been alive (for most of them), I for one believe that they belong to neither group.

antoniseb
2006-Jun-01, 06:29 PM
Thanks folkhemmet. That's pretty much my assessment too. WMAP conclusions may have some flaws, but it is probably not far wrong.

Jerry
2006-Jun-03, 09:29 PM
In the end, I believe it comes down to whether you think the WMAP team is part of the extreme optimist group or the extreme pessimist group. Given their exquisitely careful and thorough analysis of the data and more years of experience working in science than years I've been alive (for most of them), I for one believe that they belong to neither group.
...which is a reasonable position, and one that should probably be taken by anyone teaching astronomy at any except the highest levels.

Personally, I think there are credibility issues: Even after releasing data three years late, they have not addressed the many issues raised by well qualified distracters.

Astrophysics, abstract
astro-ph/0604410

From: Joao Magueijo [view email]

Date: Wed, 19 Apr 2006 16:00:05 GMT (11kb)

Occam's razor meets WMAP
http://arxiv.org/abs/astro-ph/0604410

Joao Magueijo & Rafael D. Sorkin


Using a variety of quantitative implementations of Occam's razor we examine the low quadrupole, the ``axis of evil'' effect and other detections recently made appealing to the excellent WMAP data. We find that some razors demolish the much lauded claims for departures from scale-invariance. They all reduce to pathetic levels the evidence for a low quadrupole (or any other low $\ell$ cut-off), both in the first and third year WMAP releases. The ``axis of evil'' effect is the only anomaly examined here that survives the humiliations of Occam's razor, and even then in the category of ``strong'' rather than ``decisive'' evidence. Statistical considerations aside, differences between the various renditions of the datasets remain worrying.

This next one is tongue-in-cheek and very funny:

Cosmic Conspiracies
Douglas Scott & Ali Frolop

http://arxiv.org/abs/astro-ph/0604011


This Standard Model of Cosmology has received further support from the analysis of the 3-year WMAP data, combined with information from other cosmological probes. Some of the necessary ingredients of the SMC have caused cosmologists to respond with adjectives such as ‘epicyclic’, ‘ugly’, ‘baroque’ or ‘preposterous’, and with questions such as ‘who ordered that?’

I think all these adjectives fit: Something is fundamentally wrong.

Nereid
2006-Jun-03, 11:19 PM
...which is a reasonable position, and one that should probably be taken by anyone teaching astronomy at any except the highest levels.

Personally, I think there are credibility issues: Even after releasing data three years late, they have not addressed the many issues raised by well qualified distracters.Perhaps it's just me, but I can't tell, from this, if your (implied?) barb is directed at the observations, the analyses, or the interpretations.

Can you clarify please?

In particular, are you claiming that
a) the WMAP mission is (contains) fundamental(ly) flaw(ed)?
b) the analyses of the data from the satellite have failed to address "the many issues raised by well qualified distracters"
c) the interpretation of the (cleaned) data are inconsistent with one or more big bang cosmologies?
Astrophysics, abstract
astro-ph/0604410

From: Joao Magueijo [view email]

Date: Wed, 19 Apr 2006 16:00:05 GMT (11kb)

Occam's razor meets WMAP
http://arxiv.org/abs/astro-ph/0604410

Joao Magueijo & Rafael D. SorkinI read the preprint (very interesting! thanks for bringing it to our attention!), but am puzzled ... what is it that you think this paper shows, in terms of "not address[ing] the many issues raised by well qualified distracters"?

I must have missed it; my impression, on reading it, is that they have fired a very powerful broadside into the "distracters" camp (i.e. claims of the extent to which various 'anomalies' hurt the BBTs' cases have been greatly exaggerated).

(to be continued)

Nereid
2006-Jun-04, 12:39 AM
[snip]

This next one is tongue-in-cheek and very funny:

Cosmic Conspiracies
Douglas Scott & Ali Frolop

http://arxiv.org/abs/astro-ph/0604011
[snip]VERY funny! :clap: :D

I particularly liked the "Milne coincidence" (refs 8 and 9)!

folkhemmet
2006-Jun-04, 02:10 AM
Jerry,

If something is fundamentally wrong with the SCM, as you say, then just as other things have been fundamentally wrong before in the history of science then in time what may be fundamentally wrong with the SCM will most likely be revealed. However, even the cosmologists who first revealed the "axis of evil" do not believe, as you do, that there is something fundamentally wrong with the entire Big Bang framework. You might find the following letter, in which Starkmann et al explain their position, instructive:

Cosmic Correction

15 January 2005
From New Scientist Print Edition. Subscribe and get 4 free issues.
Craig Copi Cleveland, Ohio, US, and Geneva, Switzerland

Your article "Universe map runs into local difficulty" did a good job communicating the nature of our analysis of the "oldest light in the universe", measured using WMAP, the Wilkinson Microwave Anisotropy Probe (11 December 2004, p 10). We would, however, like to offer an important clarification: we do not believe that our results "throw into question the data's relevance and accuracy". We take WMAP's data seriously, and question neither its accuracy nor its relevance. Many results derived from the data appear to us to be very robust.

The article goes on to say that we are "casting doubt on the interpretation of the data and, in turn, on some of the models that spring from it". We do believe our work and that of others casts doubt on cosmological events as the cause of the largest-scale fluctuations in the WMAP data. We also think it suggests that either some subtle contamination has crept into the data or the WMAP analysis or, more likely, that the largest-scale fluctuations are caused by some physical effect associated with the solar system or its immediate neighbourhood. However, we agree with the common interpretation of the WMAP data at smaller scales."

I agree with you that the WMAP team seemed to avoid the issue of the low-l anomalies. I hoped and expected them to have an entire paper included with the other 3-year papers in which they did their best to analyze these low-l anomalies. These low-l anomalies should not be swept under the rug. Having said that, my position is that there are scientific facts about the structure and evolution of the universe which are well-established, but the quest for a complete understanding of the cosmos will probably never cease, as these anomalies suggest. Much has been learned about the Universe through millennia of thought and observation, and much remains to be learned about the Universe. Hopefully the system of greed and power which is threatening the future of our civilization can be replaced soon so that we can continue on this fascinating odyssey into the indefinite future.

"...which is a reasonable position, and one that should probably be taken by anyone teaching astronomy at any except the highest levels."

Jerry, you are essentially saying people at the highest levels of astronomy should be what then--either extreme optimists who believe WMAP solved cosmology, or, extreme pessimists who believe that nothing is, can, or will be established in the study of the large scale structure and evolution of the Universe?

Jerry
2006-Jun-05, 06:14 PM
It should be extraordinary that the authors of this paper find it necessary to reaffirm their belief in the basic BB premise and the broader interpretations of the WMAP data, even though the jest of the data analysis that they are reporting is exactly inconsistent with these premises. I have been studying astrophysical papers for decades, and if you look for it, there is an unscientific trend: In papers where the data appears to contradict the standard model, the authors are careful to reaffirm their acceptance of the model in spite of any evidence that they have generated that is contrary. The question this raises is obvious: Since astrophysics is a highly specialized and subdivide field, whom is minding the store?

I have written about the importance of evidence of local contamination in the WMAP data as a failed 'sanity check' of the basic premise. In supernova research, there is a similar sanity check, one that supernovae type Ia analyses are also failing: the greater the redshift, the shorter the rise time of the supernova, in other words, as we look back in time, supernova explosions appear to have blossomed faster than they do now. If this were a galactic trend, it could be considered evidence of evolution, but supernovae have very specific size and spectroscopic constraints – they cannot be evolving and fit the standard model. Something systemic is wrong.

Even basic galactic evolution is failing sanity checks: As galaxies age, the ratio of size of the central core to the size of the galaxy as a whole should change; and the metal content should age. But in deep field surveys the ratio of the galactic core size to the size of the galaxy as a whole remains statistically the same, and as far back as we can see metal ratios remain more-or-less constant.

So why do cosmologists remain so confident in the basic model? The answer is we are not. We are looking for alternatives and hoping for research break-throughs that will resolve these conundrums. Will we find gravity waves? Higgs Bosons? Population III stars? Personally I am extremely optimistic that a radical solution will ultimately prove to be more correct than the current standard model, but very very few cosmologist expect this type of solution.

So when I lecture young students, I emphasize the importance of the the scientific method, and I am careful to stay within standard model constraints, but I also warn them that there are mysteries and puzzles that are not resolved, the final chapter has not been written, and if they chose to enter the field, they should do so with the expectation that there is still much to be discovered.

antoniseb
2006-Jun-05, 08:58 PM
In supernova research, there is a similar sanity check, one that supernovae type Ia analyses are also failing: the greater the redshift, the shorter the rise time of the supernova, in other words, as we look back in time, supernova explosions appear to have blossomed faster than they do now.

Do you have a pointer to this research? I've never heard this before.

Nereid
2006-Jun-05, 09:15 PM
It should be extraordinary that the authors of this paper find it necessary to reaffirm their belief in the basic BB premise and the broader interpretations of the WMAP data, even though the jest of the data analysis that they are reporting is exactly inconsistent with these premises. I have been studying astrophysical papers for decades, and if you look for it, there is an unscientific trend: In papers where the data appears to contradict the standard model, the authors are careful to reaffirm their acceptance of the model in spite of any evidence that they have generated that is contrary. The question this raises is obvious: Since astrophysics is a highly specialized and subdivide field, whom is minding the store?

I have written about the importance of evidence of local contamination in the WMAP data as a failed 'sanity check' of the basic premise.Where? I mean, where can we read about your commentary on the WMAP team's failed sanity checks?
In supernova research, there is a similar sanity check, one that supernovae type Ia analyses are also failing: the greater the redshift, the shorter the rise time of the supernova, in other words, as we look back in time, supernova explosions appear to have blossomed faster than they do now. If this were a galactic trend, it could be considered evidence of evolution, but supernovae have very specific size and spectroscopic constraints – they cannot be evolving and fit the standard model. Something systemic is wrong.I think there is a (very lengthy) thread, in BAUT's ATM section, devoted to discussion of this (and other SNe topics).
Even basic galactic evolution is failing sanity checks: As galaxies age, the ratio of size of the central core to the size of the galaxy as a whole should change; and the metal content should age. But in deep field surveys the ratio of the galactic core size to the size of the galaxy as a whole remains statistically the same, and as far back as we can see metal ratios remain more-or-less constant.Without knowing which papers/studies you are referring to, I can't say categorically that you are misrepresenting the research (but it sure feels like you have distorted things here) - which papers/observations do you have in mind here? I'm particularly interested to learn how selection effects were even estimated, much less controlled.
So why do cosmologists remain so confident in the basic model? The answer is we are not. We are looking for alternatives and hoping for research break-throughs that will resolve these conundrums. Will we find gravity waves? Higgs Bosons? Population III stars? Personally I am extremely optimistic that a radical solution will ultimately prove to be more correct than the current standard model, but very very few cosmologist expect this type of solution.Hmm, rather a sweeping generalisation, isn't it?

The good news is that resources are being devoted to further research, and with the continued improvements in all kinds of instruments, analyses, etc, the universe will have fewer and fewer places to hide its secrets.
So when I lecture young students, I emphasize the importance of the the scientific method, and I am careful to stay within standard model constraints, but I also warn them that there are mysteries and puzzles that are not resolved, the final chapter has not been written, and if they chose to enter the field, they should do so with the expectation that there is still much to be discovered.And so say all of us.

BTW, it seems that you missed several questions I asked about the content of some of your earlier posts - would you like me to repeat them? I am quite interested in the answers.

upriver
2006-Jun-15, 04:27 AM
Ouch!!!!!!!



Abstract: G1.00005 : WMAP: A Radiological Analysis II.

3:44 PM–3:56 PM

Preview Abstract
Author:

Pierre-Marie Robitaille
(The Ohio State University)

"Any ``signal'' observed by WMAP is simply the result of foreground effects not only from our galaxy, but indeed yearly variations from every galaxy in the universe. Contrary to published analysis, the argument suggests there are no findings in these images other than those related to image processing, yearly galactic variability and point sources."
http://meetings.aps.org/Meeting/NWS06/Event/50584

Zahl
2006-Jun-15, 12:31 PM
This same person (Pierre-Marie Robitaille) has also written that the 3K blackbody spectrum that COBE/FIRAS measured is in fact produced by the oceans. He also predicted that WMAP will not detect an anisotropy signal. Enough said.

http://flux.aps.org/meetings/YR01/NWS01/abs/S120004.html

Jerry
2006-Jun-15, 06:36 PM
Do you have a pointer to this research? I've never heard this before.
http://arxiv.org/abs/astro-ph/0310529

Weidong Li, Alexei V. Filippenko


Several studies raise concerns about the evolution of SNe Ia (e.g., the peculiarity rate, the risetime, and the color of SNe Ia at different redshifts), but all these studies suffer from the difficulties of obtaining high-quality spectroscopy and photometry for SNe Ia at high redshifts.

Most of the discussion on this (WMAP) topic has moved to the ATM board. It is sometimes difficult to decide what should and should not be. Generally, when the response of criticism of MS theory turns the corner from "well, ok, if this does not work, what does?' The discussion becomes ATM, because all there are are is 'maybes'.


This same person (Pierre-Marie Robitaille) has also written that the 3K blackbody spectrum that COBE/FIRAS measured is in fact produced by the oceans. He also predicted that WMAP will not detect an anisotropy signal. Enough said.
In the 'Origin of Species' Charles Darwin made at least three arguments that are now known to be false. Likewise, Newton believed in spontanious generation, and even conducted experiment to prove it. Anyone and everyone critical of scientific theory and proposing alternatives will be wrong. Not every established and ingrained theory is right. Read the arguments, challenge the content.

Zahl
2006-Jun-15, 10:39 PM
In the 'Origin of Species' Charles Darwin made at least three arguments that are now known to be false. Likewise, Newton believed in spontanious generation, and even conducted experiment to prove it. Anyone and everyone critical of scientific theory and proposing alternatives will be wrong.

Dabbling with alchemy and spontaneous creation when these things were at the cutting edge of science is one thing, but maintaining in the 21st century that the oceans give off 3K blackbody emission is something completely different. He might as well have stated that invisible little helpers put the photons in FIRAS detectors. I'm sorry Jerry, but there is a limit to what a person can say and still retain his credibility.


Read the arguments, challenge the content. And I have a suggestion for you - answer the direct questions put to you.

Zahl
2006-Jun-16, 08:37 AM
Why not start a new thread on that subject on the QA forum?

ngeo
2006-Jun-18, 02:23 PM
The complete abstract to which Upriver referred:

“Pierre-Marie Robitaille
(The Ohio State University)

“WMAP images have an exceedingly low signal to noise (just in excess of 1). Final images are made from 12 section images, which in turn are processed using separate linear combinations of data. ILC coefficients do not remain constant from year to year. In contrast to standard practices in medicine, difference images are presented at substantially reduced resolution. ILC images are not presented for year 2 and 3. Rather, year-1 data is signal averaged in the 3 year data set. Proper tests of reproducibility require viewing separate yearly ILC images. Fluctuations arise from the inability to properly remove the galactic foreground and in the significant yearly variations in the foreground itself. Variations in the map outside the galactic plane are significant, preventing any cosmological analysis due to yearly changes. This occurs despite the masking more than 300 image locations. Any ``signal'' observed by WMAP is simply the result of foreground effects not only from our galaxy, but indeed yearly variations from every galaxy in the universe. Contrary to published analysis, the argument suggests there are no findings in these images other than those related to image processing, yearly galactic variability and point sources.”

Is this so incredible it doesn’t require a response?

antoniseb
2006-Jun-18, 02:44 PM
Is this so incredible it doesn’t require a response?

I don't know. Certainly the accusation is pretty damning. I've looked on the WMAP website (as a place to start) and they do not disprove him by showing year-one data, year-two data, and year-three data all on separately computed maps. It *could* be that it is so constant that they felt there was no need to show (or even compute) such maps.

I am not an ATM supporter, but I am kind of curious to see what kind of variation there is from year to year in the map, and how large scale that variation is compared to what we're actually observing as a 'signal'.

The WMAP website doesn't make that easy information to acquire.

turbo-1
2006-Jun-18, 04:03 PM
I, too, would like to see the data mapped year-by-year. If the CMB temperature changes from one year to the next, it is proof that the CMB is not the echo of the BB, but is the temperature of "empty" space. Even the tiniest anisotropies WMAP would subtend areas of space no longer in causal contact, and it would be impossible for them to conspire to change together in the course of a year.

antoniseb
2006-Jun-18, 04:15 PM
Even the tiniest anisotropies WMAP would subtend areas of space no longer in causal contact, and it would be impossible for them to conspire to change together in the course of a year.

I don't think that changing in unison would imply current contact, but I do agree both that if the level of change is significant compared to the noise in the measurement, that it would indicate that the observed signal is not from the microwave background. However, I also think that if it is constant within the limits of the noise in the system, that we can rule out a source in the Solar neighborhood (within a few light years).

As a side note, you CAN examine the COBE data and compare it to the WMAP data, and it is pretty clear that the larger scale variations have not changed in the interval.

folkhemmet
2006-Jun-20, 05:47 PM
Obviously, the WMAP data is not perfect, nor is any other data set. There are always going to be errors and deviations from the ideal. And, yes, we may never be sure that what we know is what is. However, Pierre-Marie Robitaille, Jerry, and ATM posters should bear in mind that not all of their ideas can be correct, and they should be more willing to admit that their own ideas are subject to falsification just as are the ideas they dismiss as nonsense. A common pattern among these ATMers is this: if a finding is released which casts doubt on the Big Bang theory or CMB physics comes out, then it is automatically correct (“See, I told you so”); if a finding comes out which seems to confirm the Big Bang, then it is probably incorrect (“the methodology has to be flawed”). This pattern can be seen just by perusing the baut Story Comments section. This is known as the confirmation bias. Ironically, this type of bias is the same one which ATMers are accusing the WMAP team. They accuse the WMAP team of closed-off narrow-minded thinking and assumptions, but perhaps people who live in glass houses should not throw so many stones.

Nereid
2006-Jun-22, 01:12 AM
I, too, would like to see the data mapped year-by-year.

[snip] You wish is my command, sire

The WMAP website (http://map.gsfc.nasa.gov/index.html) has, on this page (http://map.gsfc.nasa.gov/m_mm/pub_papers/threeyear.html), a link to a paper called "Three-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Three Year Explanatory Supplement", If you click on the PDF, you get a nice big fat PDF file, which contains such intriguing chapter headings, under "Data Products" as "Full Resolution Individual Year Sky Maps", "I, Q, U, S Single Year Coadded Maps(Individual DAs)", "I, Q, U, S Single Year Maps Inverse Covariance Matrices (Individual
DAs)". In addition, section 3 ("Time Ordered Data (TOD)"), contains the following:
Three complete time-ordered data archives are supplied with the latest WMAP data release; two of these archives contain calibrated data while the second contains uncalibrated (or raw) data.
[table]
The uncalibrated archive contains all four radiometer channels for each observation; the calibrated archives have been coadded into two radiometer channels to reduce their size. The first calibrated archive has had an hourly baseline removed as part of the calibration process; the second has had a prewhitening filter applied to the data during calibration.
WMAP’s Telemetry data consists of many packet types; each packet type contains several measurements with some sort of common theme. Once on the ground and delivered to the data analysis facility, these packets are sorted and a subset are combined into records spanning 46.08 seconds; these records comprise the time-ordered data (TOD) archive. This archive is
maintained in a collection of files, each spanning one day of data.
The TOD archive is distributed to the public through daily files written using the Flexible Image Transport Standard (FITS) format.IOW, there is several (dozen) GB of WMAP data, in 46.08 second increments, fully publicly available.

Should any researcher wish to perform any time-related analyses, such as those implied by turbo-1, they are free to do so.

Nereid
2006-Jun-22, 01:19 AM
The complete abstract to which Upriver referred:

“Pierre-Marie Robitaille
(The Ohio State University)

“WMAP images have an exceedingly low signal to noise (just in excess of 1). Final images are made from 12 section images, which in turn are processed using separate linear combinations of data. ILC coefficients do not remain constant from year to year. In contrast to standard practices in medicine, difference images are presented at substantially reduced resolution. ILC images are not presented for year 2 and 3. Rather, year-1 data is signal averaged in the 3 year data set. Proper tests of reproducibility require viewing separate yearly ILC images. Fluctuations arise from the inability to properly remove the galactic foreground and in the significant yearly variations in the foreground itself. Variations in the map outside the galactic plane are significant, preventing any cosmological analysis due to yearly changes. This occurs despite the masking more than 300 image locations. Any ``signal'' observed by WMAP is simply the result of foreground effects not only from our galaxy, but indeed yearly variations from every galaxy in the universe. Contrary to published analysis, the argument suggests there are no findings in these images other than those related to image processing, yearly galactic variability and point sources.”

Is this so incredible it doesn’t require a response?I couldn't find evena preprint (so all I have to comment on is the abstract). However, the claim in the abstract is indeed bold (not to say, preposterous).

Fortunately, as the WMAP dataset is fully, publicly, available, anyone (in principle) can download the relevant data, perform their own analyses, and see for themselves just how well Pierre-Marie Robitaille's claims are matched by the WMAP data.

Whether Pierre-Marie Robitaille has performed such analyses, and how good those analyses are, must await the publication of the paper from which the abstract has been abstracted.

folkhemmet
2006-Jun-22, 08:03 PM
First of all, it is at least worth pointing out that this person is not a trained cosmologist or even a trained physicist. His scientific background is in inorganic chemistry and biochemistry. Unless one is used to grappling with astrophysical concepts on a regular basis it may be easy for them to reach incorrect conclusions which are more of a result of (i) some subtle point that they did not even think of because they lack the experience, or (ii) some point that they failed to grasp in the first place. By analogy, this is also true in athletics—a marathon runner may have great endurance overall but when he goes to compete in the mile he probably will not be able to do as well as a trained miler. This is called the principle of specificity in exercise physiology, and something like it almost certainly holds true in the scientific/intellectual arena. So, his credentials should be taken into account.

I would be just as suspicious of a WMAP team member’s conclusion about biochemistry or inorganic chemistry. The WMAP team, as far as I know, does not have expertise in these scientific areas. The fact is that most of us would not go to the WMAP team for medical care because they lack the expertise to do a really good job checking human health even though they may be equipped with enough knowledge of physics to understand somethings about the body.


Of course, the typical anti-cosmologist/radical skeptic response to this objection is that not everybody who has ever had something valuable to say in science has been trained in the specific area to which they ended up contributing. While this is sometimes the case, it is generally the case that things do not work this way. And it is more often the case that people who try to be great in many pursuits end up not doing all that well in any of them because they spread themselves too thin.

Not all ideas about the Universe’s structure and evolution are correct. One thing anti-cosmologist/radical skeptics continue to do is act as if their ideas are right on the money whereas everybody else who has spent years of thought and effort trying to understand the Universe is automatically all wrong. Since not all ideas are correct, these folks should be more willing than they clearly are to accept that their ideas are also subject to falsification.

Nereid
2006-Jun-23, 09:54 PM
WMAP images have an exceedingly low signal to noise (just in excess of 1).(my bold).

I missed this, the first few times I read it.

Perhaps the paper - when anyone can finally get a copy - will clarify in a way that makes perfect sense, but it reads like a real clanger (or, crudely, that the author really doesn't understand the WMAP data products).

IIRC, there is a figure, perhaps in a Year 1 paper, showing contours of S/N, in l-frequency space ... for much of it, the S/N ratio is way, way above 1 ....

turbo-1
2006-Jun-23, 11:32 PM
(my bold).

I missed this, the first few times I read it.

Perhaps the paper - when anyone can finally get a copy - will clarify in a way that makes perfect sense, but it reads like a real clanger (or, crudely, that the author really doesn't understand the WMAP data products).

IIRC, there is a figure, perhaps in a Year 1 paper, showing contours of S/N, in l-frequency space ... for much of it, the S/N ratio is way, way above 1 ....WMAP is mapping a VERY low temperature differential, and there are many areas that are excluded from the overall co-added map. Perhaps you can supply us with links to high-resololution difference maps that are clearly separated (Years 1, 2, and 3).

Nereid
2006-Jun-24, 12:00 PM
I missed this, the first few times I read it.

Perhaps the paper - when anyone can finally get a copy - will clarify in a way that makes perfect sense, but it reads like a real clanger (or, crudely, that the author really doesn't understand the WMAP data products).

IIRC, there is a figure, perhaps in a Year 1 paper, showing contours of S/N, in l-frequency space ... for much of it, the S/N ratio is way, way above 1 ....WMAP is mapping a VERY low temperature differential, and there are many areas that are excluded from the overall co-added map. Perhaps you can supply us with links to high-resololution difference maps that are clearly separated (Years 1, 2, and 3).My comment was on the abstract, specifically its use of the term 'image' (AFAIK, no WMAP data products are 'image's) and (apparent) inaccuracy wrt the S/N ratio.

In an earlier post, I gave links to publicly available material, from the WMAP team, from which the kinds of "high-resololution difference maps that are clearly separated (Years 1, 2, and 3)" could be derived (you would have to do the work of making the maps yourself though).

I'm sure that if some researcher has sufficient interest in producing these kinds of maps, they will appear in the literature before too long.

Jerry
2006-Jun-25, 07:31 PM
If Robitaille's claim that the year-to-year maps are incoherant is correct, WMAP is absolutely useless...unless the temperature changes are periodic, and the period can be characterized in a well-developed model.

Most of the time Folkhemmet's 'specificity' argument is valid, but there are times when the validity of the a researcher's conclusion, or in this case, a team of many researchers should be challanged: This time they should have their feet held to the fire.

An overlay of each years results should be a required, almost superficial sanity check of the data using a principle all scientists know: Are the results reproducible? If such an overlay is indeed incongruent, the WMAP team should have made it very clear why, and in the language of science we all understand, their justification for accepting this stunning result. What they have published, in this regard, wouldn't rank a white ribbon at the science fair.

As I have mentioned before, the WMAP team has not addressed issues raised by well credentialed researchers, and have chosen to ignore the 'Axis of Evil'. They are three years behind the deadline on sharing results. These are scientific credibility issues that cannot be waived off as challenges based upon ignorance. There is no room in real science for Ptolemiec arrogance.

antoniseb
2006-Jun-25, 11:25 PM
If Robitaille's claim that the year-to-year maps are incoherant is correct, WMAP is absolutely useless...unless the temperature changes are periodic, and the period can be characterized in a well-developed model.

The one-year map and the three-year map are very similar at every place that I've looked. If the data were as random and you're interperating Robitaille as saying, this could not be the case.

The WMAP team is not talking discussing this randomness you're talking about, I suspect because it isn't there. Nereid is right. the detailed data is available for you to analyze. I didn't look at the specific details yet (nor is it on my agenda). If you feel that they are being criminally negligent here, or covering up a crisis in cosmology, you probably have to get over your reluctance, and show it.

Nereid
2006-Jun-26, 12:47 AM
If Robitaille's claim that the year-to-year maps are incoherant is correct, WMAP is absolutely useless...unless the temperature changes are periodic, and the period can be characterized in a well-developed model.And if WMAP is infested with Nereid's invisible pink fairies, who maliciously insert just enough of "I Love Lucy" into the data that its presence can be detected with enough care, then WMAP is absolutely useless.
Most of the time Folkhemmet's 'specificity' argument is valid, but there are times when the validity of the a researcher's conclusion, or in this case, a team of many researchers should be challanged: This time they should have their feet held to the fire.Why?

And why not roll up your sleeves, download the TOD data, perform your own analyses, and show that Robitaille's claim that the year-to-year maps are incoherant is correct?
An overlay of each years results should be a required, almost superficial sanity check of the data using a principle all scientists know: Are the results reproducible? If such an overlay is indeed incongruent, the WMAP team should have made it very clear why, and in the language of science we all understand, their justification for accepting this stunning result. What they have published, in this regard, wouldn't rank a white ribbon at the science fair.Oh?

And how many other bold (not to say preposterous) claims should they have spent long hours nixing? How much longer should they have delayed publication, to ensure that they had addressed all the 'from left field' ideas, whether published, in preprint, or just in someone's head?
As I have mentioned before, the WMAP team has not addressed issues raised by well credentialed researchers, and have chosen to ignore the 'Axis of Evil'. They are three years behind the deadline on sharing results.My hat off to you Jerry, the smoothness of the elision from Robitaille's claim to "well credentialed researchers" and "the 'Axis of Evil'", that's a technique I must study.

But in case I misunderstood - are you (deliberately or otherwise) equating the heft of these "well credentialed researchers" and "the 'Axis of Evil'" with the credibility of Robitaille's claim? Are you, in some oblique way, giving your personal endorsement to the the soundness of the Robitaille's physics?
These are scientific credibility issues that cannot be waived off as challenges based upon ignorance. There is no room in real science for Ptolemiec arrogance.Good.

When can we extect to see your preprint, presenting an analysis of the WMAP data, in yearly increments?

Nereid
2006-Jun-26, 12:55 AM
The one-year map and the three-year map are very similar at every place that I've looked.
[snip]For the record, here (http://arxiv.org/abs/astro-ph/0302207) is the preprint containing the first year map, and here (http://xxx.lanl.gov/abs/astro-ph/0603451) is the one with the corresponding three-year map.

antoniseb
2006-Jun-26, 01:34 AM
On page 66 of your second link you can see them side by side, and it is clear that aside from some variation around the galactic plane, they are just about identical. Jerry's (or Robitaille's) claims seem pretty baseless.

Jerry
2006-Jun-26, 04:07 AM
However, Pierre-Marie Robitaille, Jerry, and ATM posters should bear in mind that not all of their ideas can be correct, and they should be more willing to admit that their own ideas are subject to falsification just as are the ideas they dismiss as nonsense.

My wife insists that I take exception to this remark: “Folkhemmet has no idea how many ideas you have tried and rejected, and how hard you try to disprove your own ideas.” Which is another way of saying, “Jerry has been wrong more often than right.” Remember that:)

The close agreement of the COBE and WMAP 1st year data is a given - they used the same or very similar foreground masks, so the residuals could be in close agreement and still have foreground-induced errors. However, the higher detail in the WMAP should also agree with the 2d and third year passes if the basic template is clean. There were obvious problems here:

http://map.gsfc.nasa.gov/m_mm/pub_papers/syserr/wmap_3yr_syserr.pdf



When the gain models fit to the first year observation data were extended to the 3-year data significant deviations became evident. These deviations became apparent as the input housekeeping data to the model (V and TFPA) spanned a larger range than was used to fit the model, due to the slow warming of the observatory. Re-fitting the original gain model parameters (V0, T0 and α) greatly improved the agreement between the model and dipole derived gain measurements, but significant errors still were evident. An additional term was added to the model to account for the variation of the compression of the amplifiers and square law diode detectors with their physical temperature by allowing the parameter characterizing the nonlinearity to have a weak temperature dependence.

I'm not sure what they are doing, but it looks like they are squeezing in another calibration coefficient that uses the first year data to recalibrate the second and third year data...I can't evaluate this without more study. It is clear the second and third year data did not agree with first year data until the gain parameters were tweaked. If this tweaking was literally sky pixel-by-sky pixel, the technique needs to be put under a microscope.


Correction of this systematic error accounts for a part of the small increase in the reported value of the quadrupole moment, ℓ(ℓ + 1)C2/2π, from 154 µK2 in the year-1 release (Bennett et al. 2003b) to 220 µK2, the largest change being the result of the change of the estimator use to evaluate the quadrupole (Hinshaw et al. 2006). It should be noted that the current value is still far smaller than the expected value of ∼ 1220µK2 obtained from the best fit _-dominated cold dark matter models (Hinshaw et al. 2006).
This is the major difference between "BB with Inflation" and observational data that lead to the adoption of the Dark Energy parameter. Yes Papageno, the theory was changed to fit the data.

P18

In other words, the model fits to near the noise of the measurement with just 152 parameters.
Their words, not mine.


These full sky maps suffer from small processing artifacts associated with observations in which one of the telescope beams is in a region of strong Galactic emission while the other is in a low Galactic emission region. These artifacts arise from slight errors in the radiometer gain determination and pixelization effects, resulting in errant signals in some high Galactic latitudes regions used in CMB analyses.

The year-1 map processing eliminated this problem by only updating the value in the pixel with the high Galactic emission for such observations in the iterative map making procedure (Hinshaw et al. 2003a).

So much for the high agreement between theory and expectations close to the galactic plane...

My hat off to you Jerry, the smoothness of the elision from Robitaille's claim to "well credentialed researchers" and "the 'Axis of Evil'", that's a technique I must study.

Ouch! that is badd....


But in case I misunderstood - are you (deliberately or otherwise) equating the heft of these "well credentialed researchers" and "the 'Axis of Evil'" with the credibility of Robitaille's claim? Are you, in some oblique way, giving your personal endorsement to the the soundness of the Robitaille's physics?

Frankly, my first and second read of the WMAP are close to Robitaille's, but I need to understand the data reduction techniques better. It would be reasonable to require the WMAP researchers to reduce the second and third year data using the exact same techniques that they did the first year data, and then run statistical and eigenvector studies of the differences.

What I am reading seems to indicate these side by side comparisions did not match, but I can't tell whether the differences are large or small, and I can't evaluate the whether the 152 parameter model is reasonable. Fermi said he could build an elephant with five free parameters. I wonder what he could do with 152.

Edit: format

Kaptain K
2006-Jun-26, 10:41 AM
...the theory was changed to fit the data.
Well...DUH!!!

That's the way science works!

What did you expect them to do? Fudge the data to fit the theory?

Jerry
2006-Jun-26, 01:23 PM
Well...DUH!!!

That's the way science works!

What did you expect them to do? Fudge the data to fit the theory?
Actually, scientist have three choices: They can reject the data as artifact, they can modify the theory, or they can throw the theory out and start over. Since the 'Dark Energy' parameter has to account for ~70% of the mass of the universe to fill the void left by the missing peak, adopting it is like saying what we thought was a snake was really just the trunk of an elephant. I would be a lot happier if the elephant were white instead of black.

folkhemmet
2006-Jun-27, 05:59 PM
Pierre's and Jerry's ideas, which are similar to one another, are both an attack on the view that much can be learned about the Universe from what some cosmologists refer to as the "cosmic Rosetta stone." This is evident from the vocabulary they use to describe the WMAP results. If I am reading their view correctly, it amounts to this: the CMB is not cosmological and is generated by sources in the nearby Universe. According to them, the CMB signal is an amalgam of signals from solar, galactic, and extragalactic sources, or as Pierre puts it, "every galaxy in the Universe."

Their view is the denial of the popular conception, almost universally accepted by lots of bright cosmologists, that the hot and cold spots in the microwave background are the seeds of galaxy clusters and voids. They do not believe that the slight differences in the density of the early Universe led to the cosmic web we appear to be immersed in today. In fact, I am not sure either of these two skeptics believe there was an early Universe, or, if they do believe that there was an early Universe, then they believe our view of it is being censored by our solar system and/or galaxy.

I am not a cosmologist, but one way I can think of testing Jerry's view is a way that will probably never be funded by our civilization--that is, we should try to see what the microwave sky looks like from as many places in the Universe as possible.

If the CMB fluctuations outside of the galactic plane are identical in other solar systems, then we can at least rule out Jerry's theory that the CMB is generated by stars and their immediate surroundings. However, if the CMB fluctuations look different in each solar system we measure them from this would confirm Jerry's idea that the CMB is generated by stars and their immediate surroundings. Afterall, if the CMB fluctuations are what gave rise to galaxy clusters and voids which, according to the popular view, are now ~45 billion light years away, then the fluctuations should look the same to onlookers in different Milky Way planetary systems. Communications with extraterrestrials would help our effort; other civilizations could send us their maps of the CMB, assuming they made them.

antoniseb
2006-Jun-27, 09:19 PM
That's an interesting idea. I expect that in a few decades, that if we create high energy spacecraft for getting people transported from Earth to Mars in a few weeks instead of several months, that we will be able to simple release probes on trajectories out of the Solar System much faster than New Horizons. We could use a few of those to launch Planck-like probes to collect this sort of data from outside the Heliopause.

Zahl
2006-Jul-05, 09:30 AM
You wish is my command, sire

The WMAP website (http://map.gsfc.nasa.gov/index.html) has, on this page (http://map.gsfc.nasa.gov/m_mm/pub_papers/threeyear.html), a link to a paper called "Three-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Three Year Explanatory Supplement", If you click on the PDF, you get a nice big fat PDF file, which contains such intriguing chapter headings, under "Data Products" as "Full Resolution Individual Year Sky Maps", "I, Q, U, S Single Year Coadded Maps(Individual DAs)", "I, Q, U, S Single Year Maps Inverse Covariance Matrices (Individual
DAs)". In addition, section 3 ("Time Ordered Data (TOD)"), contains the following:IOW, there is several (dozen) GB of WMAP data, in 46.08 second increments, fully publicly available.

Should any researcher wish to perform any time-related analyses, such as those implied by turbo-1, they are free to do so.

You don't need to do any analysis to get your hands on the year-by-year maps as they are available right here:

http://lambda.gsfc.nasa.gov/product/map/current/m_products.cfm

The "raw" full resolution (12.58 million pixels) Stokes I parameter (total intensity) sky maps are at "High Resolution I Maps per D/A". The maps are calibrated and the dipole has been removed, but they are unsmoothed, unweighted and with full unreduced foregrounds. Unfortunately the maps are in the HEALPix FITS format and the HEALPix software package

http://healpix.jpl.nasa.gov/

used in professional CMB analysis or the SkyViewer program

http://lambda.gsfc.nasa.gov/toolbox/tb_skyviewer_ov.cfm

must be used to look at them. Both are freely available, but must be compiled from the sources. There are Windows viewers that support the FITS format, but none that I know of to support HEALPix.

Zahl
2006-Jul-05, 09:35 AM
The complete abstract to which Upriver referred:

“Pierre-Marie Robitaille
(The Ohio State University)

“WMAP images have an exceedingly low signal to noise (just in excess of 1). Final images are made from 12 section images, which in turn are processed using separate linear combinations of data. ILC coefficients do not remain constant from year to year. In contrast to standard practices in medicine, difference images are presented at substantially reduced resolution. ILC images are not presented for year 2 and 3. Rather, year-1 data is signal averaged in the 3 year data set. Proper tests of reproducibility require viewing separate yearly ILC images. Fluctuations arise from the inability to properly remove the galactic foreground and in the significant yearly variations in the foreground itself. Variations in the map outside the galactic plane are significant, preventing any cosmological analysis due to yearly changes. This occurs despite the masking more than 300 image locations. Any ``signal'' observed by WMAP is simply the result of foreground effects not only from our galaxy, but indeed yearly variations from every galaxy in the universe. Contrary to published analysis, the argument suggests there are no findings in these images other than those related to image processing, yearly galactic variability and point sources.”

Is this so incredible it doesn’t require a response?

You only need to look at the well known angular power spectrum to see that the signal to noise ratio is >> 1.

ngeo
2006-Jul-27, 11:10 PM
“Our best estimate of the power spectrum is derived from 28 cross-power spectra of statistically independent channels. The final spectrum is essentially independent of the noise properties of an individual radiometer.”

First-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: The Angular Power Spectrum (Hinshaw et al)

I doubt that the three-year interpretation is any different than this.

garykpo
2007-Apr-29, 11:21 PM
just wanted to introduce myself im an idealist who is lookin for some new friends to contimplate the universe please excuse my spelling and please feel free to share your opinions on anything related to science. i crave knoledge and am interested in anyone who might have radical views or vast knoledge on scientific info etc. thanks

Jerry
2007-Apr-30, 06:14 PM
Pierre's and Jerry's ideas, which are similar to one another, are both an attack on the view that much can be learned about the Universe from what some cosmologists refer to as the "cosmic Rosetta stone." This is evident from the vocabulary they use to describe the WMAP results. If I am reading their view correctly, it amounts to this: the CMB is not cosmological and is generated by sources in the nearby Universe. According to them, the CMB signal is an amalgam of signals from solar, galactic, and extragalactic sources, or as Pierre puts it, "every galaxy in the Universe."

...

If the CMB fluctuations outside of the galactic plane are identical in other solar systems, then we can at least rule out Jerry's theory that the CMB is generated by stars and their immediate surroundings. However, if the CMB fluctuations look different in each solar system we measure them from this would confirm Jerry's idea that the CMB is generated by stars and their immediate surroundings. Afterall, if the CMB fluctuations are what gave rise to galaxy clusters and voids which, according to the popular view, are now ~45 billion light years away, then the fluctuations should look the same to onlookers in different Milky Way planetary systems. Communications with extraterrestrials would help our effort; other civilizations could send us their maps of the CMB, assuming they made them.

Pierre-Marie Robitaille's contention that the CMB is contaminated by oceanic microwave noise can easily be tested by the PLANCK probe. Oddly, again according to Marie, this was not testable by WMAP, because the detectors were differential, providing no absolute temperature reference relative the COBE and earth-based results.

As far as Jerry's 'local foreground' hypothesis goes:

http://www.physorg.com/news96301312.html


According to Kronberg, "One of the most exciting aspects of the discovery is the new questions it poses. For example, what kind of mechanism could create a cloud of such enormous dimensions that does not coincide with any single galaxy, or galaxy cluster? ...And separately, could the newly discovered fluctuating radio glow be related to unwanted foregrounds of the Cosmic Microwave Background (CMB) radiation?"

But I like the idea of independant confirmation by extra terrestrials better.

Peter Wilson
2007-Apr-30, 08:18 PM
...But I like the idea of independant confirmation by extra terrestrials better.I like the idea too, but so-far ETs have not even phoned to say "Hi," let alone confirm our astrophysical measurements :think:

SETI (http://setiathome.ssl.berkeley.edu/)