Generation of particle number asymmetry in expanding universe

Abstract

We study creation and time evolution of particle number asymmetry with nonequilibrium quantum field theory. We introduce a model of a neutral scalar and a complex scalar and it has CP violating and particle number violating features. Starting with an initial condition specified by density operator, we show how particle number asymmetry can be generated through interaction. We investigate the time evolution of particle number asymmetry of universe using perturbation method.

Comments: 5 pages, 2 figures, contributed talk at 1st Workshop on Phenomenology for Particle and Anti-Particle 2018, minor modification