Gravitational Waves from Hidden QCD Phase Transition

TL;DR

This paper explores how a hidden QCD-like sector undergoing a chiral phase transition can generate gravitational waves detectable by future space-based observatories, providing a test for certain scale-invariant extensions of the Standard Model.

Contribution

It introduces a novel mechanism linking hidden QCD phase transitions to observable gravitational waves, using the Nambu--Jona-Lasinio method for estimation.

Findings

GW signals are within reach of future space-based detectors.

The model connects early universe phase transitions to testable gravitational wave signatures.

Provides a new probe for scale-invariant extensions of the Standard Model.

Abstract

Drastic changes in the early universe such as first-order phase transition can produce a stochastic gravitational wave (GW) background. We investigate the testability of a scale invariant extension of the standard model (SM) using the GW background produced by the chiral phase transition in a strongly interacting QCD-like hidden sector, which, via a SM singlet real scalar mediator, triggers the electroweak phase transition. Using the Nambu--Jona-Lasinio method in a mean field approximation we estimate the GW signal and find that it can be tested by future space based detectors.