Original scientific paper

Nonsingular cosmological models with a variable cosmological term Λ

Anirudh Pradhan ; Department of Mathematics, Hindu Post-graduate College, Zamania-232 331, Ghazipur, India
Kashika Srivastava ; Department of Mathematics, Hindu Post-graduate College, Zamania-232 331, Ghazipur, India
Amrit Lal Ahuja ; Inter-University Centre for Astronomy and Astrophysics, Ganeshkhind, Pune-411 007, India

Abstract

Exact solutions of the Einstein's field equations describing a spherically symmetric cosmological model without a big bang or any other kind of singularity recently obtained by Dadhich and Patel (2000) are revisited. The matter content of the model is a shear-free perfect fluid with isotropic pressure and a radial heat flux. Three different exact solutions are obtained both for perfect fluid and fluid with bulk viscosity. It turns out that the cosmological term Λ(t) is a decreasing function of time, which is consistent with recent observations of type Ia supernovae.

Keywords

non-singular models; cosmology; variable cosmological constant; causality principle

Hrčak ID:

304467

URI

https://hrcak.srce.hr/304467

Publication date:

1.7.2007.

Article data in other languages: croatian

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