Homogeneous isotropic cosmological models with pseudoscalar torsion function in Poincare gauge theory of gravity and accelerating Universe

TL;DR

This paper explores how pseudoscalar torsion in Poincare gauge gravity models can naturally produce an accelerating universe, offering a geometric explanation for dark energy without introducing new fields.

Contribution

It develops homogeneous isotropic cosmological models with pseudoscalar torsion in Poincare gauge theory, showing they can generate effective cosmological constants and acceleration.

Findings

Models exhibit late-time acceleration due to torsion effects.

Effective cosmological constant emerges from torsion-related parameters.

Acceleration is linked to the geometrical properties of space-time torsion.

Abstract

The "dark energy" problem is investigated in the framework of the Poincare gauge theory of gravity in 4-dimensional Riemann-Cartan space-time. By using general expression for gravitational Lagrangian homogeneous isotropic cosmological models with pseudoscalar torsion function are built and investigated. It is shown that by certain restrictions on indefinite parameters of gravitational Lagrangian the cosmological equations at asymptotics contain effective cosmological constant and can lead to observable acceleration of cosmological expansion. This effect has geometrical nature and is connected with space-time torsion.