Scalar induced gravitational waves in PV symmetric teleparallel gravity with non-minimally coupled boundary term

TL;DR

This paper explores how parity violation in symmetric teleparallel gravity affects scalar induced gravitational waves, revealing detectable deviations from general relativity at high frequencies.

Contribution

It introduces a non-minimally coupled boundary term to avoid strong coupling issues and studies the resulting SIGWs in PV symmetric teleparallel gravity.

Findings

SIGW energy density spectrum deviates from GR predictions at high frequencies

Deviations are detectable by future space-based GW detectors

Non-minimally coupled boundary term resolves strong coupling problem

Abstract

The question of whether the parity violation occurs in gravitational interaction has recently attracted much attention. In this paper, we investigate the scalar induced gravitational waves (SIGWs) in symmetric teleparallel gravity incorporating a parity-violating (PV) term and a non-minimally coupled boundary term. The presence of this non-minimally coupled boundary term help to avoid the strong coupling problem inherent in PV symmetric teleparallel gravity, thereby enabling our study of the SIGWs in this PV symmetric teleparallel gravity. We calculate the SIGWs generated during the radiation-dominated era and compute the corresponding energy density spectrum with a monochromatic primordial power spectrum, numerically. The resulting energy density spectrum of SIGWs exhibits significant deviations from that is predicted by general relativity, particularly at high frequencies. This different feature is detectable by future space-based GW detectors like LISA, TianQin and Taiji.