Axion Dark Matter in High Scale Inflation Scenario

Abstract

QCD axion introduced to solve the strong CP problem of the Standard Model of particle physics is one of the most compelling candidates for dark matter in the universe. The speaker will discuss the cosmological constraints on axion dark matter in a more generic context than the previous discussion, taking into account that the axion scale can have a nontrivial cosmological evolution. He will also propose a noble supersymmetric axion model in which the axion isocurvature perturbation generated during the primordial high scale inflation is diluted by a late thermal inflation, while still a right amount of axion dark matter is achieved by the conventional misalignment mechanism.