Gravitational Waves at Strong Coupling from an Effective Action

TL;DR

This paper derives an effective action holographically to analyze gravitational wave signals from phase transitions at strong coupling, highlighting potential observability at LISA for TeV-scale temperatures.

Contribution

It introduces a holographic method to compute quasi-equilibrium parameters for gravitational waves from strong coupling phase transitions, linking them to the dual field theory's degrees of freedom.

Findings

Potential LISA detection at TeV-scale temperatures.

Parameter variation with degrees of freedom analyzed.

Approximate conformal symmetry enhances signal prospects.

Abstract

Using a holographic derivation of a quantum effective action for a scalar operator at strong coupling, we compute quasi-equilibrium parameters relevant for the gravitational wave signal from a first order phase transition in a simple dual model. We discuss how the parameters of the phase transition vary with the effective number of degrees of freedom of the dual field theory. Our model can produce an observable signal at LISA if the critical temperature is around a TeV, in a parameter region where the field theory has an approximate conformal symmetry.