Institute for Advanced Study Informal Astrophysics Seminar

ABSTRACT: I will describe a new, generic mechanism for realizing a period of slowly-rolling inflation through the use of an analog of 'magnetic drift.' I will focus on a particular realization of this mechanism - Chromo-Natural Inflation - which consists of an axion coupled to non-Abelian gauge fields. The model's novel requirement is that the gauge fields begin inflation with a rotationally invariant vacuum expectation value (VEV) that is preserved through identification of SU(2) gauge invariance with rotations in three dimensions. The gauge VEV interacts with the axion leading to an attractor solution that exhibits slow-roll inflation even when the axion potential is steep. I will show that the background gauge fields mediate parity-violating interactions in the action for the fluctuations leading to observable gravitational waves with a preferred handedness.