Cosmological Constant and Gravitational Repulsion Effect: 1. Homogeneous models with radiation

TL;DR

This paper investigates how a cosmological constant within a Poincare gauge gravity framework can induce gravitational repulsion, leading to non-singular homogeneous cosmological models with radiation.

Contribution

It demonstrates that including a cosmological constant in Poincare gauge gravity can cause gravitational repulsion and yields explicit non-singular solutions for homogeneous radiation models.

Findings

Cosmological constant can induce gravitational repulsion.

Explicit non-singular solutions are derived.

Models exhibit non-singular behavior with radiation.

Abstract

Within the framework of the minimum quadratic Poincare gauge theory of gravity in the Riemann-Cartan spacetime we study the influence of gravitational vacuum energy density (a cosmological constant) on the dynamics of various gravitating systems. It is shown that the inclusion of the cosmological term can lead to gravitational repulsion. For some simple cases of spatially homogeneous cosmological models with radiation we obtain non-singular solutions in form of elementary functions and elliptic integrals.