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arXiv · 1711.01961

Intrinsic Entropy Perturbations from the Dark Sector

Marco Celoria·Denis Comelli·Luigi Pilo
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Abstract

Perfect fluids are modeled by using an effective field theory approach which naturally gives a self-consistent and unambiguous description of the intrinsic non-adiabatic contribution to pressure variations. We study the impact of intrinsic entropy perturbation on the superhorizon dynamics of the curvature perturbation ${\cal R}$ in the dark sector. The dark sector, made of dark matter and dark energy is described as a single perfect fluid. The non-perturbative vorticity's dynamics and the Weinberg theorem violation for perfect fluids are also studied.

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Marco Celoria, Denis Comelli, Luigi Pilo. 2017-11-03. Intrinsic Entropy Perturbations from the Dark Sector. https://doi.org/10.1088/1475-7516%2F2018%2F03%2F027

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