Particle Production and Density Fluctuations of Non-classical Inflaton in Coherent Squeezed Vacuum State of Flat FRW Universe

TL;DR

This paper investigates the behavior of a non-classical inflaton in a flat FRW universe within a coherent squeezed vacuum state, analyzing oscillations, fluctuations, and particle production, and assessing the validity of semiclassical gravity equations.

Contribution

It introduces a detailed analysis of non-classical inflaton dynamics and quantum fluctuations in a coherent squeezed vacuum state, extending understanding of early universe quantum effects.

Findings

Scale factor proportional to t^{2/3} in CSVS

Quantum fluctuations independent of coherent parameter

Particle production studied for oscillating inflaton

Abstract

We study non-classical inflaton, which is minimally coupled to the semiclassical gravity in FRW universe in Coherent Squeezed Vacuum State (CSVS). We determined Oscillatory phase of inflaton, power-law expansion, scale factor, density fluctuations, quantum fluctuations and particle production for CSVS. We obtained an estimated leading solution of scale factor in CSVS proportional to $t^{2/3}$ follow similar diversification as demonstrated by Semiclassical Einstein Equation (SCEE) of gravity in matter dominated universe. We also studied the validity of SCEE in CSVS. By determining the quantum fluctuation for CSVS validity of uncertainty relation for FRW Universe also computed. The results shows that Quantum fluctuations doesn't depend on coherent parameter $\Upsilon$ as uncertainty relation doesn't effected by the displacement of $\Upsilon$ in phase space. We study the production of particles in CSVS for oscillating massive inflaton in flat FRW universe.