Inflationary cosmology with scalar field and radiation

TL;DR

This paper proposes a self-consistent inflationary cosmology model driven by scalar field decay, producing radiation without reheating, and matching thermodynamic and entropy constraints.

Contribution

It introduces a novel exact model of quantum radiation creation during inflation, avoiding reheating and ensuring thermodynamic consistency.

Findings

Radiation produced obeys standard thermodynamics.

The model smoothly transitions from inflation to radiation era.

Total entropy aligns with accepted cosmological values.

Abstract

We present a simple, exact and self-consistent cosmology with a phenomenological model of quantum creation of radiation due to decay of the scalar field. The decay drives a non-isentropic inflationary epoch, which exits smoothly to the radiation era, without reheating. The initial vacuum for radiation is a regular Minkowski vacuum. The created radiation obeys standard thermodynamic laws, and the total entropy produced is consistent with the accepted value. We analyze the difference between the present model and a model with decaying cosmological constant previously considered.