APEC + ICRR seminar

Speaker: Alexander Kusenko (Kavli IPMU/UCLA)
Title: Higgs relaxation and leptogenesis
Date (JST): Wed, Nov 12, 2014, 13:30 - 14:30
Place: Seminar Room A
Related File: 1298.pdf
Abstract: I will discuss a new avenue for leptogenesis. The recent measurement of the Higgs boson mass implies a relatively slow rise of the Standard Model Higgs potential at large scales. A scalar field with such a potential develops a large vacuum expectation value at the end of inflation. The relaxation of the Higgs field from its large postinflationary value to the minimum of the effective potential represents an important stage in the evolution of the universe. During the Higgs relaxation, the time-dependent Higgs condensate can create an effective chemical potential for the lepton number, leading to a generation of the lepton asymmetry in the presence of some large right-handed Majorana neutrino masses. The electroweak sphalerons redistribute this asymmetry between leptons and baryons. The Higgs relaxation leptogenesis can explain the observed matter-antimatter asymmetry of the universe even if the Standard Model is valid up to the scale of inflation, and any new physics is suppressed by that high scale. The epoch of Higgs relaxation might have other observable consequences, for example, primordial magnetic fields.