Energy Density, Temperature and Entropy Dynamics in Perturbative Reheating

Understand

We discuss the perturbative decay of the energy density of a non standard inflaton field $\rho_{\phi}$ and the corresponding creation of the energy density of the relativistic fields $\rho_r$ at the end of inflation, in the perfect fluid description, refining some concepts and providing some new computations.

• In particular, the process is characterized by two fundamental time scales.
• The first one, $t_\text{max}$, occurs when the energy density $\rho_r$ reaches its largest value, slightly after the beginning of the reheating phase.
• The second one, $t_\text{reh}$, is the time in which the reheating is completely realized and the thermalization is attained.