Effect of new string loop corrections on type IIB string inflation

This Master thesis is focused on the study of the inflationary dynamics coming from new corrections added to the standard LVS framework used in the context of moduli stabilisation in type IIB string compactifications on Calabi-Yau orientifolds. The closed string sector of the 4D effective supergravity theory features 3 classes of moduli: the dilaton which sets the string coupling, the complex structure moduli which parameterise the shape of the extra dimensions, and the Kaehler moduli whose vacuum expectation value controls the size of the extra dimensions. At tree-level the dilaton and the complex structure moduli are stabilised supersymmetrically in terms of 3-form flux quanta. On the other hand, the Kaehler moduli are flat directions due to the underlying no-scale cancellation. It is therefore important to study which perturbative or non-perturbative correction to the effective action generates the leading order no-scale breaking effect. Several contributions have been studied in the past ranging from ED3 instantons, gaugino condensation, alpha' corrections and string loops. In this Master thesis we will focus in particular on new string loop corrections to the Kaehler potential which have been derived recently by Antoniadis and collaborators. These corrections introduce a Kaehler moduli-depedent logarithmic shift of the Calabi-Yau volume that breaks the no-scale structure. We analyse the effect of these new corrections on known moduli stabilisation scenarios like KKLT and LVS and then study its repercussions on cosmological and inflationary quantities in order to make some realistic predictions and match experimental data.