Leptogenesis from Pseudo-Scalar Driven Inflation

TL;DR

This paper critically evaluates claims of significant leptogenesis during inflation via gravitational anomalies, demonstrating that proper inclusion of short-distance effects reduces the expected lepton asymmetry.

Contribution

It clarifies the impact of short-distance contributions on leptogenesis predictions, challenging previous estimates of large lepton asymmetry.

Findings

Lepton asymmetry is smaller than previously claimed when short-distance effects are included.

Proper treatment of gravitational anomalies reduces the expected leptogenesis.

Previous models overestimated lepton number generation during inflation.

Abstract

We examine recent claims for a considerable amount of leptogenesis, in some inflationary scenarios, through the gravitational anomaly in the lepton number current. We find that when the short distances contributions are properly included the amount of lepton number generated is actually much smaller.