Gravitational Waves from Hidden QCD Phase Transition

Understand

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.