1996/06/26 by Mar Bastero-Gil, Bastero-Gil, M., Biswajoy Brahmachari +3
Computer Science · #Advanced Data Storage Technologies #Computability, Logic, AI Algorithms #Cryptography and Data Security #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph)
paper · pdf · doi:10.48550/arxiv.hep-ph/9606447
openalex publication_date 1996/06/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The nature of R-parity violating interactions in two classes of string inspired supersymmetric grand unified theories (SISUSY GUT), based on the gauge groups SO(10) (and its subgroup SU(2)L× SU(2)R× SU(4)c≡ G224) as well as [SU(3)]3, are discussed and their strengths are related to the ratio of symmetry breaking scales present in the model. We first argue that for the R-parity violating couplings λR / to be suppressed to the desired level, the B-L local symmetry must break at an intermediate scale MB-L since λR / =MB-L/MGUT. We then construct scenarios where such intermediate scales arise being consistent with gauge coupling unification in a two-loop renormalization group study. In the resulting SO(10) models, higher-dimensional-operator-induced R-parity violating couplings are potentially large (except in one case), and are therefore inconsistent with limits on the proton life time unless the couplings associated with the higher dimensional terms are fine tuned to very small values. However, the [SU(3)]3 and G224 models can be consistent if a certain class of quark-lepton coupling in the superpotential is forbidden by a discrete summetry (unrelated to R-parity). An interesting prediction of these models is neutron-anti-neutron oscillation with observable strength.