Inflation and Dark Matter in the $Z_5$ Model

Abstract: We discuss the possibility of unifying dark matter physics and inflation in the $Z_5$ model of the two-component dark matter. Inflation driven by the two-component dark matter fields can be divided into two cases, singlet dark matter inflation and mixed dark matter inflation, where both two-component play the role of inflaton in the latter case. For dark matter, we focus on the mixed dark matter inflation case. We show a viable parameter space that satisfies the theoretical and dark matter relic density constraint in the case of successful inflation. It turns out that the dark matter density is dominated by the light component, which is consistent with the feature of the $Z_5$ model of the two-component dark matter.