Constraint on the Squeeze Parameter of Inflaton from Cosmological Constant

TL;DR

This paper constrains the squeeze parameter of the inflaton field after inflation by interpreting the relic inflaton's energy density as an effective cosmological constant and comparing it with observational data.

Contribution

It introduces a novel approach to constrain the inflaton's squeeze parameter using the relic inflaton's contribution to the cosmological constant.

Findings

Derived bounds on the inflaton squeeze parameter from observational data

Link between squeezed vacuum state and effective cosmological constant

Implications for inflationary models and early universe physics

Abstract

The inflaton is highly likely to settle in a squeezed vacuum state after inflation. The relic inflaton after inflation and reheating undergoes a damped oscillatory motion and contributes to the effective cosmological constant. We interpret the renormalized energy density from the squeezed vacuum state as an effective cosmological constant. Using the recent observational data on the cosmological constant, we find the constraint on the squeeze parameter of the inflaton in the early universe.