Sterile neutrinos, $0\nu\beta\beta$ decay and the W-boson mass anomaly in a Flipped $SU(5)$ from F-theory

We investigate the low energy properties of an effective local model with flipped $SU(5)\times U(1)_{\chi }$ gauge group, constructed within the framework of F-theory. Its origin is traced back to the SO(10) symmetry – associated with a geometric singularity of the compactification manifold – broken by an internal flux which is turned on along the seven-brane in the $U(1)_{\chi }$ direction. Topological properties and the choice of flux parameters determine the massless spectrum of the model to be that of the minimal flipped SU(5) supplemented with an extra right-handed electron-type state and its complex conjugate, $E^c+{{\bar{E}}}^c$, as well as neutral singlet fields. The subsequent symmetry breaking to the $SU(3)\times SU(2)\times U(1)_Y$ gauge group occurs with a Higgs pair in $10+{\overline{10}}$ representations of SU(5). Next we proceed to the phenomenological analysis of the resulting effective model and the salient outcomes are: The $E^c+{{\bar{E}}}^c$ pair acquires a mass of few TeV and as such could solve the $g_{\mu }-2$ discrepancy. Neutrino couplings to extra neutral singlets lead to an inverse seesaw mechanism where an extra light state could be a suitable dark matter candidate. The predictions of the model for the ${0\nu }\beta \beta $ decay rate could be tested in near future experiments. There are non-unitarity deviations from the lepton mixing matrix $(U_{PMNS}),$ which could in principle explain the new precision measurement of the W-boson mass recently reported by the CDF II collaboration.