Gravitational waves and magnetic monopoles during inflation with Weitzenb\"ock torsion

TL;DR

This paper investigates how torsion in an extended geometric framework influences the generation of magnetic monopoles and gravitational waves during cosmic inflation, suggesting boundary terms as potential sources for these phenomena.

Contribution

It introduces a novel approach linking boundary conditions and torsion to the emergence of magnetic monopoles and gravitational waves in an inflationary universe.

Findings

Boundary terms can generate a cosmological constant.

Torsion acts as a source for magnetic monopoles.

Gravitational waves can be produced during inflation.

Abstract

We study the variational principle on a Hilbert-Einstein action in an extended geometry with torsion taking into account non-trivial boundary conditions. We obtain an effective energy-momentum tensor that has its source in the torsion, which represents the matter geometrically induced. We explore about the existence of magnetic monopoles and gravitational waves in this torsional geometry. We conclude that the boundary terms can be identified as possible sources for the cosmological constant and torsion as the source of magnetic monopoles. We examine an example in which gravitational waves are produced during a de Sitter inflationary expansion of the universe.