Some Issues in Flat Direction Baryogenesis

TL;DR

Anisimov and Dine address the problem of predicting the baryon asymmetry in Affleck-Dine baryogenesis in the presence of thermal effects in the early universe. They show that finite-temperature masses, evaporation rates, and thermal A terms can dominate the condensate dynamics, altering the produced asymmetry relative to zero-temperature estimates. They provide $n=1$--$4$ analyses with $W_n = \phi^{n+3} / M^n$, finding that $n=1$ typically underproduces, $n=2$ can be viable depending on the reheat temperature $T_R$, and $n\ge 3$ can yield substantial asymmetries even after thermal corrections; they also discuss whether Q-balls can form and survive the thermal history, concluding that evaporation often erases condensates and possibly Q-balls depending on $n$. The work emphasizes the importance of finite-temperature dynamics for accurate predictions of the matter–antimatter asymmetry and Q-ball phenomenology in SUSY cosmology.

Abstract

Motivated by recent developments, we explore some issues in Affleck-Dine baryogenesis. We consider in greater detail the role of thermal effects in the production of baryon number. We find that these effects are important even for rather flat potentials, and obtain somewhat different estimates of the baryon asymmetry than those in the literature. We also consider the decay of the condensate, and possible implications of these observations for the formation of Q-balls.