Chaotic inflation and a radiatively generated intermediate scale in the supersymmetric standard model

We consider a phenomenological extension of the minimal supersymmetric standard model which incorporates chaotic inflation and a radiatively generated intermediate mass scale. Initially a period of chaotic inflation is driven by a quartic potential associated with the right-handed electron sneutrino. Supersymmetry relates the quartic coupling of the inflationary potential to the electron Majorana neutrino Yukawa coupling, h₁. The microwave background temperature anisotropy determines this coupling to be h₁ {reversed tilde equals} 10^-7, which is similar in magnitude to the electron Dirac Yukawa coupling. A U(1) Peccei-Quinn (PQ) symmetry is broken by radiative corrections at an intermediate scale {reversed tilde equals} 10¹² GeV when the universe cools to a temperature T ≲ 10³ GeV. This leads to an invisible axion, a weak scale μ-term and an electron Majorana neutrino mass M_N1 {reversed tilde equals} 10⁵ GeV. A second inflationary period can also occur via a flat-direction field. In this case the universe can be reheated to a temperature T_RH {reversed tilde equals} 10⁶GeV, without restoring PQ symmetry. Baryogenesis will then occur via out-of-equilibrium neutrino decay.