Abstract

I shall show how to combine moduli stabilisation and SU(5)- or MSSM -like chiral models in a fully consistent global set-up in Type IIB /F-theory by considering compactifications on Calabi-Yau orientifolds which admit an explicit description in terms of toric geometry. I shall present explicit choices of brane set-ups and fluxes which lead to three different phenomenological scenarios: the first with GUT -scale strings and TeV-scale SUSY ; the second with an exponentially large value of the internal volume and TeV-scale SUSY without fine-tuning the background fluxes; and the third with a very anisotropic configuration that leads to TeV-scale strings and two micron-sized extra dimensions. The fibred structure of the Calabi-Yau three-fold is also particularly suitable for cosmological purposes.