Non-universal Z′Z' from Fluxed GUTs

We make a first systematic study of non-universal TeV scale neutral gauge bosons $Z'$ arising naturally from a class of F-theory inspired models broken via $SU(5)$ by flux. The phenomenological models we consider may originate from semi-local F-theory GUTs arising from a single $E_8$ point of local enhancement, assuming the minimal ${\cal Z}_2$ monodromy in order to allow for a renormalisable top quark Yukawa coupling. We classify such non-universal anomaly-free $U(1)'$ models requiring a minimal low energy spectrum and also allowing for a vector-like family. We discuss to what extent such models can account for the anomalous $B$-decay ratios $R_{K}$ and $R_{K^*}$.Comment: 14 page

Topics on modern String phenomenology

In this thesis we present phenomenological consequences of the modern nonperturbative regimes of String Theory, M- and F-Theory. The origins of SO(10) from M-Theory on G2 manifolds are discussed, accompanied by a detailed discussion on a rank-breaking mechanism and consequences for neutrino masses. The Minimal Supersymmetric Standard Model is derived from F-Theory compactifications exhibiting a spectral cover equation with Klein monodromy and a geometric parity that endows the spectrum with an effective matter parity. A dedicated and systematic study on R-Parity violating couplings in F-Theory is also presented, where we find these couplings to be generic, and we compute their magnitudes