(P)reheating and gravitational waves in α-attractor models

Abstract We study post-inflationary evolution in α -attractor T-models of inflation. consider the dynamics both scalar fields present these models: inflaton and spectator, as a negative field-space curvature may lead to geometrical destabilization spectator. perform state-of-the-art lattice simulations with dedicated numerical code optimized for those models. corroborate earlier findings that perturbations spectator field are much more unstable than field, so early stages preheating is dominated by perturbations. also calculate spectrum gravitational waves originating from fluctuations order determine if can be constrained or even ruled out cosmological observations, but not direct searches waves.