Primordial gravitational waves in non-minimally coupled chromo-natural inflation
Emanuela Dimastrogiovanni, Matteo Fasiello, Martino Michelotti, Lucas Pinol
Abstract
Abstract We consider inflation driven by an axion-like particle coupled to an SU(2) gauge sector via a Chern-Simons term. Known as chromo-natural inflation, this scenario is in tension with CMB observations. In order to remedy this fact and preserve both the symmetries and the intriguing gravitational wave phenomenology exhibited by the model, we explore the non-minimal coupling of the axion-inflaton to the Einstein tensor. We identify regions of parameter space corresponding to a viable cosmology at CMB scales. We also highlight the possibility of a non-trivial chiral gravitational wave signal at small scales.
Topics & Concepts
PhysicsInflation (cosmology)Gravitational waveNatural (archaeology)Primordial black holeAstrophysicsTheoretical physicsHistoryArchaeologyBinary black holeCosmology and Gravitation TheoriesSolar and Space Plasma DynamicsGeophysics and Gravity Measurements