Supersymmetry breaking
We propose a new mechanism of (geometric) moduli stabilisation in type IIB/F-theory four-dimensional compactifications on Calabi-Yau manifolds, in the presence of 7-branes, that does not rely on non-perturbative effects. Complex structure moduli and the axion-dilaton system are
stabilised in the standard way, without breaking supersymmetry, using 3-form internal fluxes. K”ahler class moduli...
I will discuss the role of lepton flavour in scalar triplet leptogenesis, a mechanism for the generation of the baryon asymmetry of the Universe involving a heavy scalar triplet, which decays in a CP-violating way into leptons and antileptons. I will show that the effects of the different lepton flavours can never be neglected, and that their proper description at high temperature requires...
Supersymmetry breaking in heterotic strings and corrections to gauge couplings
I will discuss gauge threshold corrections in (non)supersymmetric heterotic vacua. After a general introduction to the general structure of these thresholds and to their universality properties, even in the absence of supersymmetry, I will present new vacua (supersymmetric and not) which do not suffer from the decompactification problem.
We propose a new mechanism of (geometric) moduli stabilisation in type IIB/F-theory four-dimensional compactifications on Calabi-Yau manifolds, in the presence of 7-branes, that does not rely on non-perturbative effects. Complex structure moduli and the axion-dilaton system are stabilised in the standard way, without breaking supersymmetry, using 3-form internal fluxes. K”ahler class moduli...