Speaker
Description
The transition from the inflationary phase to a radiation-dominated universe is typically a complex problem. The post-inflationary coherent oscillations of the inflaton field can drive the resonant growth of bosonic field fluctuations, including those of the inflaton itself, leading to backreaction and non-linear effects, and the eventual fragmentation of the homogeneous inflaton. These dynamics, however, often fail to exhaust the inflaton energy density, with the conventional solution invoking a perturbative decay channel into fermions to ensure complete reheating. In this talk we re-examine this assumption, demonstrating that the coupling to fermions is not a guaranteed pathway to thermalization when Pauli-blocking effects are fully accounted beyond the Boltzmann approximation. In particular, for non-quadratic inflaton potentials, the path to a fully reheated universe is more constrained than previously assumed, necessitating a more nuanced treatment of the final phase of reheating.