  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.
