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arXiv · 2412.02276

Viscous cosmological fluids and large-scale structure

BG Mbewe·RR Mekuria·S Sahlu·A Abebe
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Abstract

In this paper, we study the viscous fluid cosmological model that when certain conditions are invoked mimics the $\Lambda$CDM model. The background equations governing the evolution of viscous interacting fluids in a multifluid system are derived. The Markov Chain Monte Carlo (MCMC) simulation is applied to constrain the best-fit cosmological parameters with Supernova Type 1a data. In addition, linear cosmological perturbations are investigated in a dust-matter-dominated frame using a $1+3$ covariant formalism approach. It is evident from the perturbation results obtained that the model predicts the disintegration of bound structures of large-scale structures in the late-time universe.

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BG Mbewe, RR Mekuria, S Sahlu, A Abebe. 2024-12-03. Viscous cosmological fluids and large-scale structure. https://arxiv.org/abs/2412.02276

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