Universe (Jan 2023)

Perturbations in Bianchi-V Spacetimes with Varying Λ, <i>G</i> and Viscous Fluids

  • Amare Abebe,
  • Alnadhief H. A. Alfedeel,
  • Değer Sofuoğlu,
  • Eltegani I. Hassan,
  • Rishi Kumar Tiwari

DOI
https://doi.org/10.3390/universe9020061
Journal volume & issue
Vol. 9, no. 2
p. 61

Abstract

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As a follow-up of a recent article in which we investigated the cosmological background expansion history of the universe in Bianchi type-V cosmological models with bulk viscous fluid and evolving cosmological Λ and Newtonian G parameters, we study the evolution of the cosmological perturbations in the current work. In particular, we analyse the evolution of the viscous matter over-density that leads to formation of large-scale structures in the Bianchi-V model, and compare the results with standard ΛCDM solutions. Our results suggest that introducing viscous fluid in the background described by Bianchi-V geometry with evolving Λ and G amplifies the structure-growth rate.

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