Parity-violation in bouncing cosmology

TL;DR

This paper explores how bouncing cosmology can amplify parity-violation signals, particularly during the high-energy bouncing phase, offering a way to probe new physics at this scale.

Contribution

It identifies the bouncing phase as the primary source of parity-violation signals, highlighting its potential to reveal new physics at high energies.

Findings

Bouncing phase dominates parity-violation signal generation.

Contraction phase contributes less to parity-violation.

High-energy bouncing phase allows probing new physics.

Abstract

We investigate the possibility of the enhancement of parity-violation signal in bouncing cosmology. Specifically, we are interested in deciding which phase should generate the most significant parity-violation signals. We find that the dominant contribution comes from the bouncing phase, while the contraction phase has a smaller contribution. Therefore, bouncing cosmology can enhance the parity-violation signals during the bouncing phase. Moreover, since the bouncing phase has the highest energy scale in bouncing cosmology, we can also probe new physics at this scale by studying the parity-violation effect.