Leptogenesis from Spin-Gravity Coupling Following Inflation

TL;DR

This paper proposes a novel mechanism where gravitational waves from inflation induce a neutrino energy level splitting, leading to lepton asymmetry and subsequently baryon asymmetry through lepton number violation and sphaleron processes.

Contribution

It introduces a new leptogenesis scenario based on spin-gravity coupling during inflation, linking gravitational waves to matter-antimatter asymmetry.

Findings

Neutrino energy levels are split by gravitational waves during inflation.

Lepton asymmetry is generated at equilibrium via lepton number violating interactions.

A comparable baryon asymmetry results from sphaleron processes.

Abstract

The energy levels of the left and the right handed neutrinos is split in the background of gravitational waves generated during inflation which in presence of lepton number violating interactions gives rise to a net lepton asymmetry at equilibrium. Lepton number violation is achieved by the same dimension five operator which gives rise to neutrino masses after electro-weak symmetry breaking. A net baryon asymmetry of the same magnitude can be generated from this lepton asymmetry by electroweak sphaleron processes.