TY  - GEN
N2  - In this thesis we investigate the feasibility and phenomenology of transplanckian field displacements
during Inflation as well as the production of very light fields during Reheating.
We begin by focusing on realisations of axion inflation in the complex structure moduli
sector of Type IIB String Theory (ST) flux compactifications. Firstly, we analyse the problem
of backreaction of complex structure moduli on the inflationary trajectory in a concrete model
of axion monodromy inflation. Secondly, we propose a realisation of natural inflation where the
inflaton arises as a combination of two axions. In both cases we find sufficiently flat inflationary
potentials over a limited, but transplanckian field range. However, our realisation of axion
monodromy inflation requires a potentially large, though realisable, number of tunings to ensure
that the inflationary shift symmetry is only weakly broken.
The consequences of the Weak Gravity Conjecture (WGC) for axion monodromy inflation
are then explored. We find that the conjecture provides a bound on the inflationary field range,
but does not forbid transplanckian displacements. Moreover, we provide a strategy to generalise
the WGC to general p-form gauge theories in ST.
Finally, we focus on the physics of the early post-inflationary phase. We show that axion
monodromy inflation can lead to a phase decomposition, followed by the radiation of potentially
detectable gravitational waves. We also propose a strategy to evade the overproduction of Dark
Radiation in the Large Volume Scenario of moduli stabilisation, by means of flavour branes
wrapping the bulk cycle of the compactification manifold.
AV  - public
A1  - Rompineve Sorbello, Fabrizio
ID  - heidok22904
Y1  - 2017///
TI  - Imprints of Quantum Gravity on Large Field Inflation and Reheating
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/22904/
ER  -