Quintessential Affleck-Dine baryogenesis with non-minimal couplings

TL;DR

This paper proposes a new Affleck-Dine baryogenesis model that leverages non-minimal couplings and a kinetic dominated era to generate the Universe's baryon asymmetry without producing isocurvature fluctuations.

Contribution

It introduces a novel Affleck-Dine scenario involving non-minimal gravity coupling and a kinetic era, avoiding isocurvature fluctuations and enabling baryon asymmetry generation.

Findings

Heavy Affleck-Dine field during inflation prevents isocurvature fluctuations.

Tachyonic effective mass during kinetic era allows large field expectation values.

Inverse phase transition triggers baryon asymmetry generation.

Abstract

We present a novel Affleck-Dine scenario for the generation of the observed baryon asymmetry of the Universe based on the non-trivial interplay between quintessential inflationary models containing a kinetic dominated post-inflationary era and a non-minimally coupled $U(1)$ field with a weakly broken $B-L$ symmetry. The non-minimal coupling to gravity renders heavy the Affleck-Dine field during inflation and avoids the generation of isocurvature fluctuations. During the subsequent kinetic era the Ricci scalar changes sign and the effective mass term of the Affleck-Dine field becomes tachyonic. This allows the field to dynamically acquire a large expectation value. The symmetry of the Affleck-Dine potential is automatically restored at the onset of radiation domination, when the Ricci scalar approximately equals zero. This inverse phase transition results in the coherent oscillation of the scalar field around the origin of its effective potential. The rotation of the displaced Affleck-Dine field in the complex plane generates a non-zero $B-L$ asymmetry which can be eventually converted into a baryon asymmetry via the usual transfer mechanisms.