Chiral global embedding of Fibre Inflation with $\overline{\rm D3}$ uplift

TL;DR

This paper constructs a detailed model of Fibre Inflation in type IIB string theory with chiral matter and uplift to de Sitter space, analyzing stability and observational viability.

Contribution

It provides an explicit example of a chiral global embedding of Fibre Inflation with $ar{ m D3}$ uplift, including detailed moduli stabilization and phenomenological analysis.

Findings

Identified regions with controlled effective field theory for inflation.

Demonstrated stabilization of Kähler moduli with chiral matter effects.

Achieved a de Sitter vacuum compatible with observational constraints.

Abstract

We carefully analyse the challenges posed by the construction of type IIB chiral global embeddings of Fibre Inflation with $\overline{ \rm D3}$ uplift to a de Sitter vacuum. We present an explicit example involving an $h^{1,1}=4$ Calabi-Yau manifold with a K3 fibration and a del Pezzo divisor supporting non-perturbative effects. The chosen orientifold involution induces O3-planes that can be placed on top of each other at the tip of the throat of a deformed conifold singularity. The D7-brane sector contains standard magnetised branes and a Whitney brane. The former induce chiral matter and generate quantum effects that stabilise the K\"ahler moduli, while the latter helps to increase the total D3-charge. We study in detail the constraints on the parameter space leading to an observationally viable inflationary dynamics, finding several regions where the effective field theory is under control.