We analyze to which extent the KKLT proposal for the construction of de Sitter vacua in
string theory is quantitatively controlled. Our focus is on the quality of the 10d supergravity …

The real world as we know it happens at energies well below the Planck scale, so it is very
well described by effective field theory. There is a continuous infinity of consistent effective …

We argue that dS vacua in the LARGE-volume scenario of type IIB string theory are
vulnerable to various unsuppressed curvature, warping and gs corrections. We work out in …

A bstract The large volume scenario (LVS) for de Sitter compactifications of the type IIB string
is, at least in principle, well protected from various unknown corrections. The reason is that …

These lecture notes are devoted to formal and phenomenological aspects of F-theory. We
begin with a pedagogical introduction to the general concepts of F-theory, covering classic …

A bstract The classification of 4D reflexive polytopes by Kreuzer and Skarke allows for a
systematic construction of Calabi-Yau hypersurfaces as fine, regular, star triangulations …

The existence of Abelian gauge symmetries in four-dimensional F-theory compactifications
depends on the global geometry of the internal Calabi-Yau four-fold and has important …

We systematically analyse globally consistent SU (5) GUT models on intersecting D7-branes
in genuine Calabi–Yau orientifolds with O3-and O7-planes. Beyond the well-known tadpole …

A bstract We elaborate on recent results regarding the self-consistency of de Sitter vacua in
the LARGE-volume scenario of type IIB string theory. In particular, we analyze to what extent …

We construct global F-theory GUT models on del Pezzo surfaces in compact Calabi–Yau
fourfolds realized as complete intersections of two hypersurface constraints. The …