CMB Angular Distribution: Understanding Gaussian Random Fields

[Madster]

Dear all,

I don't understand why the Cosmic Microwave Background's angular distribution is considered to to a Gaussian random field initially.
The rest of the analysis is roughly clear to me, COBE/WMAP/PLANCK measure the CMB Photons and show the temperature fluctuations w.r.t. the mean temperature. On this data a spherical analysis is applied... But where does the GRF come from? What is b.t.w. a geometrical meaning of a GRF?

Thank you very much

 

[Mordred]

This article may help you hope your math is good lol

http://www.astro.rug.nl/~weygaert/tim1publication/lss2007/computerIII.pdf

the main usage in the CMB is in measurements of the CMB power spectrum.

 

[Madster]

This article may help you hope your math is good lol

http://www.astro.rug.nl/~weygaert/tim1publication/lss2007/computerIII.pdf

the main usage in the CMB is in measurements of the CMB power spectrum.

thanks, my math is sufficient enough to get the script. So still what mechanism makes the CMB a gaussian random field, or to be more precise, let's us initially approximate the description with a GRF and look for fluctuations?

 

[Mordred]

Gaussian random fields is an area I'm weak in however I did take bit of time researching its usages in CMB. I have some related articles in my data base that I plan on studying at some point.

http://background.uchicago.edu/~whu/Presentations/cmblens.pdf

http://background.uchicago.edu/~whu/papers/hudedval06.pdf

http://physics.stackexchange.com/questions/9106/what-exactly-is-meant-by-the-gaussianity-of-cmbr

http://www.lorentz.leidenuniv.nl/~vitelli/ThomasPNAS.pdf

hope those help