Article

# Gauge invariant Boltzmann equation and the fluid limit

• ##### Cyril Pitrou
Classical and Quantum Gravity (Impact Factor: 3.56). 07/2007; DOI: 10.1088/0264-9381/24/24/001
Source: arXiv

ABSTRACT This article investigates the collisionless Boltzmann equation up to second order in the cosmological perturbations. It describes the gauge dependence of the distribution function and the construction of a gauge invariant distribution function and brightness, and then derives the gauge invariant fluid limit.

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