Gravitational Stability of inflaton and torsion in Einstein-Cartan-Klein-Gordon cosmology with kinky potentials

TL;DR

This paper investigates the gravitational stability of torsion and inflaton fields in a de Sitter universe within Einstein-Cartan-Klein-Gordon cosmology, highlighting conditions for stability consistent with astrophysical observations.

Contribution

It derives evolution equations for torsion and inflaton fields using a Lagrangian approach in a scalar-tensor cosmology with propagating torsion, analyzing stability modes.

Findings

Stable torsion modes align with absence of relic torsion in cosmic background.

Torsion and inflaton stability depends on background field values.

Astrophysical data favor stable torsion configurations.

Abstract

Gravitational stability of torsion and inflaton field in a four-dimensional spacetime de Sitter solution in scalar-tensor cosmology where Cartan torsion propagates is investigated in detail. Inflaton and torsion evolution equations are derived by making use of a Lagrangean method. Stable and unstable modes for torsion and inflatons are found to be dependent of the background torsion and inflaton fields. Present astrophysical observations favour a stable mode for torsion since this would explain why no relic torsion imprint has been found on the Cosmic Background Radiation in the universe.