Inflation and dark matter in two Higgs doublet models

Understand

We consider the Higgs inflation in the extension of the Standard Model with two Higgs doublets coupled to gravity non-minimally.

• In the presence of an approximate global U(1) symmetry in the Higgs sector, both radial and angular modes of neutral Higgs bosons drive inflation where large non-Gaussianity is possible from appropriate initial conditions on the angular mode.
• We also discuss the case with single-field inflation for which the U(1) symmetry is broken to a Z_2 subgroup.
• We show that inflationary constraints, perturbativity and stability conditions restrict the parameter space of the Higgs quartic couplings at low energy in both multi- and single-field cases.