Speaker
Marco Nardecchia
Description
We investigate the possibility of obtaining large (up to O(1)) R-parity- and baryon-number- violating couplings in supersymmetric GUT. Since quarks and leptons are embedded into the same grand-unified multiplets, the natural expectation is that baryonic R-parity violation is always associated with similar-size lepton-number-violating couplings. Being the simultaneous presence of both types of couplings severely constrained by matter stability, the idea of grand unification may appear incompatible with the existence of large baryonic R-parity-violating interactions. On the other hand, an asymmetry between baryon- and lepton-number violating couplings can be generated after the grand-unified symmetry breaking. We study the natural implementation of such a mechanism in SU(5) and SO(10) models and comment on their phenomenological implications.
