Frontiers in Astronomy and Space Sciences (Aug 2022)

A cosmological model with time dependent Λ, G and viscous fluid in general relativity

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

DOI
https://doi.org/10.3389/fspas.2022.965652
Journal volume & issue
Vol. 9

Abstract

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In this paper, we investigate Bianchi type − V cosmological models with bulk viscous fluid and time varying cosmological Λ and Newtonian G parameters. The Einstein’s field equations have been transformed into a coupling non-linear, first-order differential equations, and the fourth-order Runge-Kutta method of numerical integration has been used to integrate the differential equations with appropriate initial conditions consistent with current cosmological observations. We show that the model describes a universe that starts off with a negative cosmological term, as well as a matter-dominated and decelerated early epoch that, eventually becomes Λ-dominated and expanding with acceleration, in concordance with current observations.

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