Speaker
Description
We study the dynamics of a spatially homogeneous scalar (or pseudoscalar) condensate Yukawa-coupled to N_f fermionic degrees of freedom, with emphasis on the real-time processes governing misalignment, particle production, and entropy generation. Going beyond the effective potential framework, we develop a dynamical treatment in which the scalar condensate and fermionic sector are evolved self-consistently within a Hamiltonian formulation that preserves energy conservation and incorporates backreaction. In the large-N_f limit, the fermionic fluctuations provide a controlled quantum bath that drives dissipative and non-adiabatic effects in the condensate dynamics. We implement a systematic adiabatic expansion to separate instantaneous effective potential contributions from genuine dynamical effects such as particle production, field renormalization, and memory-dependent corrections. We show that Yukawa interactions lead to significant fermion production, which in turn induces damping and reshaping of the condensate evolution. The resulting energy transfer generates entropy and drives the system toward a highly excited late-time regime characterized by non-thermal particle distributions and scaling behavior. In this framework, the standard effective potential emerges as the leading adiabatic approximation, while higher-order terms encode irreversible dynamics absent in equilibrium descriptions. Our results demonstrate that misaligned condensates coupled to fermions can exhibit emergent nonequilibrium phenomena, including dynamical symmetry breaking and entropy growth, highlighting the importance of fully real-time treatments in cosmological and particle physics settings where scalar fields interact with fermionic sectors.