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arXiv · 1408.7116

Temperature fluctuations in an inhomogeneous diffusive fluid

Z. Haba
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Abstract

We discuss metric perturbations of the relativistic diffusion equation around the homogeneous Juttner equilibrium of massless particles in a homogeneous expanding universe. The metric perturbation describes matter distribution and the gravitational wave background in an inhomogeneous universe. We show that the lowest order perturbation can be treated as a variation of temperature. We derive a formula expressing temperature fluctuations in terms of the diffusion and tensor power spectrum. We discuss the multipole expansion of the fluctuations in the presence of diffusion.

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Z. Haba. 2015-02-25. Temperature fluctuations in an inhomogeneous diffusive fluid. https://doi.org/10.1142/s0217732315500364

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