Related papers: Monodromy Charge in D7-brane Inflation
We investigate multi-field inflationary scenarios with fields that drop out of the model in a staggered fashion. This feature is natural in certain multi-field inflationary setups within string theory; for instance, it can manifest itself…
The unwinding inflation mechanism is studied in a type IIB flux compactification where all moduli are stabilized using flux, non-perturbative effects, and the leading alpha' corrections of the large volume scenario. We consider the…
We show that inflation which is dominated by the D-term density avoids the `slow-roll' problem of inflation in supergravity. Such an inflationary scenario can naturally emerge in theories with non-anomalous or anomalous U(1) gauge symmetry.…
We provide a pedagogical overview of inflation in string theory. Our theme is the sensitivity of inflation to Planck-scale physics, which we argue provides both the primary motivation and the central theoretical challenge for the subject.…
We investigate a new way of realizing a period of cosmological inflation in the context of brane gas cosmology. It is argued that a gas of co-dimension one branes, out of thermal equilibrium with the rest of the matter, has an equation of…
In this note we demonstrate that chaotic inflation can naturally be realized in the context of an anomaly free minimal gauged supergravity in D=6 which has recently been the focus of some attention. This particular model has a unique…
We study the slow-roll inflationary dynamics in a self-gravitating induced gravity braneworld model with bulk cosmological constant. For E \gg M_{5}^{3}/M^{2}_{2} we find important corrections to the four-dimensional Friedmann equation…
Large field inflation is arguably the simplest and most natural variant of slow-roll inflation. Axion monodromy may be the most promising framework for realising this scenario. As one of its defining features, the long-range polynomial…
We examine the relaxion mechanism in string theory. An essential feature is that an axion winds over $N \gg 1$ fundamental periods. In string theory realizations via axion monodromy, this winding number corresponds to a physical charge…
We develop a new class of supergravity cosmological models where inflation is induced by terms in the K\"ahler potential which mix a nilpotent superfield $S$ with a chiral sector $\Phi$. As the new terms are non-(anti)holomorphic, and hence…
Motivated by the possibility of inflation in the cosmic landscape, which may be approximated by a complicated potential, we study the density perturbations in multi-field inflation with a random potential. The random potential causes the…
We explore a new class of supersymmetric models of inflation where the inflaton is realised as a combination of a Higgs field and (gauge non-singlet) matter fields, using a "tribrid" structure of the superpotential. Inflation is associated…
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…
We consider DBI inflation with a quadratic potential and the effect of trapped branes on the inflationary fluctuations. When going through a trapped brane the effective potential of the inflaton receives a contribution whose effect is to…
"Brane supersymmetry breaking" occurs in String Theory when the only available combinations of D-branes and orientifolds are not mutually BPS and yet do not introduce tree-level tachyon instabilities. It is characterized by the emergence of…
Brane inflation and the production of topological defects at the end of the inflationary phase are discussed. After a description of the inflationary setup we discuss the properties of the cosmic strings produced at the end of inflation.…
We present a new model of D-term dominated chaotic inflation in supergravity. The F-flat direction present in this model is lifted by the dominant D-term, which leads to chaotic inflation and subsequent reheating. No cosmic string is formed…
We describe a model of P-term inflation on D5 branes wrapped on resolved and deformed $A_n$ type singularities. On the brane world--volume the resolution and deformation of the singularity correspond to an anomalous D-term and a linear term…
We propose a model of inflation in the framework of brane cosmology driven by background supergravity. Starting from bulk supergravity we construct the inflaton potential on the brane and employ it to investigate for the consequences to…
Cosmic inflation driven by the vacuum energy associated with the $D$-term of a supersymmetric abelian gauge group and a possible existence of long-range force mediated by an ultra-light gauge boson $Z^\prime$ are two extreme examples of…