Axion Inflation, Proton Decay and Leptogenesis in $SU(5)\times U(1{)}_{PQ}$

Abstract

We implement inflation in a non-supersymmetric SU(5) model based on a non-minimal coupling of the axion field to gravity. The isocurvature fluctuations are adequately suppressed, axions comprise the dark matter, proton lifetime estimates are of order 8e34-3e35 years, and the observed baryon asymmetry arises via non-thermal leptogenesis. The presence of low scale colored scalars ensures unification of the Standard Model gauge couplings and also helps in stabilizing the electroweak vacuum.

Comments: 8 pages, 4 figures. v2: matches published version in PRD