Kai Schmitz

Spontaneous B–L breaking as the origin of the hot early universe

Abstract The decay of a false vacuum of unbroken B – L symmetry is an intriguing and testable mechanism to generate the initial conditions of the hot early universe. If B – L is broken at the grand unification scale, the false vacuum phase yields hybrid inflation, ending in tachyonic preheating. The dynamics of the B – L breaking Higgs field and thermal processes produce an abundance of heavy neutrinos whose decays generate entropy, baryon asymmetry and gravitino dark matter. We study the phase transition for the full supersymmetric Abelian Higgs model. For the subsequent reheating process we give a detailed time-resolved description of all particle abundances. The competition of cosmic expansion and entropy production leads to an intermediate period of constant ‘reheating’ temperature, during which baryon asymmetry and dark matter are produced. Consistency of hybrid inflation, leptogenesis and gravitino dark matter implies relations between neutrino parameters and superparticle masses. In particular, for a gluino mass of 1 TeV, we find a lower bound on the gravitino mass of 10 GeV.

Predicting θ 13 and the neutrino mass scale from quark lepton mass hierarchies

A bstractFlavour symmetries of Froggatt-Nielsen type can naturally reconcile the large quark and charged lepton mass hierarchies and the small quark mixing angles with the observed small neutrino mass hierarchies and their large mixing angles. We point out that such a flavour structure, together with the measured neutrino mass squared differences and mixing angles, strongly constrains yet undetermined parameters of the neutrino sector. Treating unknown

Chaotic inflation with a fractional power-law potential in strongly coupled gauge theories

\mathcal{O}

Dynamical chaotic inflation in the light of BICEP2

(1) parameters as random variables, we obtain surprisingly accurate predictions for the smallest mixing angle,

Peccei-Quinn symmetry from a gauged discrete R symmetry

{\text{si}}{{\text{n}}^{{2}}}{2}{\theta_{{{13}}}} = 0.0{7}_{{ - 0.05}}^{{ + 0.11}}

Entropy, baryon asymmetry and dark matter from heavy neutrino decays

, the smallest neutrino mass,

Leptogenesis via Axion Oscillations after Inflation

{m_{{1}}} = {2}.{2}_{{ - {1}.{4}}}^{{ + 1.7}} \times {1}{0^{{ - {3}}}}{\text{eV}}

Matter and dark matter from false vacuum decay

, and one Majorana phase,

Superconformal D-Term Inflation

{\alpha_{{{21}}}}/\pi = {1}.0_{{ - 0.2}}^{{ + 0.2}}.