Speaker
sarben sarkar
(King's College London)
Description
We consider a model of an expanding Universe in string theory that yields CPT violation for fermions, in the sense of different dispersion relations for fermions and antifermions. These are induced by a cosmological background with constant torsion provided by the Kalb–Ramond antisymmetric tensor field (axion) of the string gravitational multiplet. This effect induces different densities of neutrinos and antineutrinos while in chemical equilibrium, offering new scenarios for leptogenesis and baryogenesis even in the absence of CP violation. Leptogenesis effects are visible at tree level and are discussed.
Primary author
sarben sarkar
(King's College London)
Co-authors
Marco de Cesare
(King's College London)
Prof.
Nikos Mavromatos
(University of London (GB))
