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arXiv · astro-ph/0312227

Characteristic Angular Scales in Cosmic Microwave Background Radiation

F. Ghasemi·A. Bahraminasab·M. Sadegh Movahed·Sohrab Rahvar·K. R. Sreenivasan·M. Reza Rahimi Tabar
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Abstract

We investigate the stochasticity in temperature fluctuations in the cosmic microwave background (CMB) radiation data from {\it Wilkinson Microwave Anisotropy Probe}. We show that the angular fluctuations of the temperature is a Markov process with a {\it Markov angular scale}, $Θ_{\rm Markov}=1.01^{+0.09}_{-0.07}$. We characterize the complexity of the CMB fluctuations by means of a Fokker-Planck or Langevin equation and measure the associated Kramers-Moyal coefficients for the fluctuating temperature field $T(\hat n)$ and its increment, $ΔT =T(\hat n_1) - T(\hat n_2)$. Through this method we show that temperature fluctuations in the CMB has fat tails compared to a Gaussian distribution.

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F. Ghasemi, A. Bahraminasab, M. Sadegh Movahed, Sohrab Rahvar, K. R. Sreenivasan, M. Reza Rahimi Tabar. 2006-11-09. Characteristic Angular Scales in Cosmic Microwave Background Radiation. https://doi.org/10.1088/1742-5468%2F2006%2F11%2Fp11008

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