CTP Seminar
Primordial gravitational waves (GWs) offer a unique window into the early universe, carrying imprints of cosmic inflation and reheating. This seminar explores their production through three key mechanisms: (1) quantum fluctuations during inflation, generating a nearly scale-invariant spectrum; (2) graviton bremsstrahlung during reheating, producing a high-frequency GW background; and (3) non-perturbative dynamics like parametric resonance, enhancing GW amplitudes. We discuss how future detectors (LISA, BBO) could distinguish these signals, probing inflation models and reheating physics beyond current limits.