2021/07/31 by Eric Gonzalez, Gordon Kane, K. Nguyen +1
Physics and Astronomy · #Black Holes and Theoretical Physics #Electron #Lepton #MAJORANA #Moduli #Neutrino #Neutrino Physics Research #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum mechanics #Quark #hep-ph #hep-th
paper · pdf · doi:10.1103/physrevd.105.046019
arxiv created 2021/11/18 · openalex publication_date 2022/02/25 · openalex created_date 2022/03/02 · arxiv updated 2022/03/14 · openalex updated_date 2026/06/26
M-theory compactified on a G2 manifold with resolved E8 singularity is a promising candidate for a unified theory. The experimentally observed masses of quarks and charged leptons put a restriction on the moduli of the G2 manifold. These moduli in turn uniquely determine the Dirac interactions of the neutrinos. In the paper, we explicitly compute the Dirac terms for neutrino mass matrix using the moduli from a localized model with resolved E8 singularities on a G2 manifold. This is a novel approach as the Dirac terms are not assumed but derived from the structure of quarks' and charged leptons' masses. Using known mass splittings and mixing angles of neutrinos, we show the acceptable region for Majorana terms. We also analyse the theoretical region for Majorana terms induced from the expectation values of right handed neutrinos through the Kolda-Martin mechanism. The intersection of the two regions indicates a restriction on neutrino masses. In particular, the lightest neutrino must have small but non-zero mass. Moreover, this also puts constraints on possible Majorana contributions from Kähler potential and superpotential, which can be traced down to a restriction on the geometry.We conclude that the masses of the two heavier light neutrinos are about 0.05 eV and 0.009 eV (0.05 eV and 0.05 eV )) for normal (inverted) hierarchy. In both hierarchies, we predict the light neutrinos are mostly Dirac type. Hence neutrino-less double-beta decay will be small. This is a testable result in a near future. Some bounds on heavy neutrinos are also derived.