Lawrence Berkeley National Laboratory — Theory Group

Inflaton decays into bosons require non-perturbative treatment because resonance and Bose enhancement invalidate a simple Boltzmann description. Fermionic decays are often assumed perturbative because Pauli blocking limits occupation numbers. Adriana Menkara examines why this expectation fails for potentials with a quartic minimum once inflaton fragmentation is included. Non-perturbative effects can halt reheating for Yukawa couplings as small as approximately 10⁻⁸; avoiding this requires couplings large enough that radiative corrections become concerning. The talk assesses the resulting obstruction to fermionic reheating and possible ways around it.