Seminarium "Teoria cząstek elementarnych i kosmologia"

Scalar condensation and its decay plays important roles in cosmology.A notable example is inflation and reheating driven by inflaton condensation and its decay. Two approaches can be found in literatures, in computing the decay (damping) rate of coherently oscillating scalar. One is based on the parametric resonance in a mode function of a daughter particle. The other is based on the effective action in the presence of a background field. In this talk, we see that these two approaches look very different in the course of computation, but actually give the same decay rate.