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arXiv · 0812.2610

Statistical mechanics of gravitating systems: An Overview

T. Padmanabhan
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Abstract

I review several issues related to statistical description of gravitating systems in both static and expanding backgrounds. After briefly reviewing the results for the static background, I concentrate on gravitational clustering of collisionless particles in an expanding universe. In particular, I describe (a) how the non linear mode-mode coupling transfers power from one scale to another in the Fourier space if the initial power spectrum is sharply peaked at a given scale and (b) the asymptotic characteristics of gravitational clustering which are independent of the initial conditions. Numerical simulations as well as analytic work shows that power transfer leads to a universal power spectrum at late times, somewhat reminiscent of the existence of Kolmogorov spectrum in fluid turbulence.

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T. Padmanabhan. 2009-02-16. Statistical mechanics of gravitating systems: An Overview. https://arxiv.org/abs/0812.2610

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