Inflationary entanglement

TL;DR

This paper explores how geometric effects during inflation can generate entanglement in particle creation, with implications for dark matter and the early universe's inhomogeneities.

Contribution

It introduces a novel inflationary model where particle production is purely geometric, linking entanglement entropy to spacetime perturbations and dark matter candidates.

Findings

Nonzero entanglement entropy from geometric particle production

Modeling particle candidates as dark matter

Quantification of back-reaction effects in slow-roll regime

Abstract

We investigate the entanglement due to geometric corrections in particle creation during inflation. To do so, we propose a single-field inflationary scenario, nonminimally coupled to the scalar curvature of spacetime. We require particle production to be purely geometric, setting to zero the Bogolubov coefficients and computing the $S$ matrix associated to spacetime perturbations, which are traced back to inflaton fluctuations. The corresponding particle density leads to a nonzero entanglement entropy whose effects are investigated at primordial time of Universe evolution. The possibility of modeling our particle candidate in terms of dark matter is discussed. The classical back-reaction of inhomogeneities on the homogeneous dynamical background degrees of freedom is also studied and quantified in the slow-roll regime.