Dark-fluid constraints of shear-free universes

Amare Abebe

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arXiv · 2205.11471

Dark-fluid constraints of shear-free universes

Amare Abebe

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Abstract

Integrability conditions arising from general irrotational fluid-flow considerations of a universe dominated by cosmic dark fluids will be investigated under special assumptions on the nature of the spacetime shear. Special emphasis will be placed on linearized perturbations of quasi-Newtonian and anti-Newtonian spacetimes, whereby the conditions for the existence and consistent evolution of such spacetimes in the presence of the Chaplygin gas fluid model will be derived and discussed.

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Amare Abebe. 2022-05-23. Dark-fluid constraints of shear-free universes. https://arxiv.org/abs/2205.11471

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