Sources of Primordial Gravitational Waves as Probe of Particle Physics

In this talk I describe various primordial sources of Gravitational Waves: inflationary tensor perturbations, primary and secondary, reheating, (p)reheating, phase transitions, cosmic strings, domain walls. I will show how a stochastic background of Gravitational Waves (SBGW) spectrum from such sources of cosmic origin acts as complementary tests of particle physics models compared to other laboratory searches and astrophysical observations.