Related papers: Perturbative K\"ahler Moduli Inflation
We propose a scenario for realizing super-Planckian axion decay constants in Calabi-Yau orientifolds of type IIB string theory, leading to large-field inflation. Our construction is a simple embedding in string theory of the mechanism of…
Achieving full moduli stabilisation in type IIB string compactifications for generic Calabi-Yau threefolds with hundreds of K\"ahler moduli is notoriously hard. This is due not just to the very fast increase of the computational complexity…
We present a new approximation scheme that allows us to increase the accuracy of analytical predictions of the power spectra of inflationary perturbations for two specific classes of inflationary models. Among these models are chaotic…
We study the influence of anomalous U(1) symmetries and their associated D-terms on the vacuum structure of global field theories once they are coupled to N=1 supergravity and in the context of string compactifications with moduli…
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…
We propose an inflationary scenario, M-flation, in which inflation is driven by three $N\times N$ hermitian matrices $\Phi_i, i=1,2,3$. The inflation potential of our model, which is strongly motivated from string theory, is constructed…
We explore the mechanics of inflation in simplified extra-dimensional models involving an inflaton interacting with the Einstein-Maxwell system in two extra dimensions. The models are Goldilocks-like in that they are just complicated enough…
We review the effects of heavy scalar fields during inflation in the framework of $\mathcal N = 1$ supergravity. Such heavy scalars can be geometric moduli from string compactifications or stabilizer fields from a different sector of the…
We propose the natural inflation from the heterotic string theory on "Swiss-Cheese" Calabi-Yau manifold with multiple $U(1)$ magnetic fluxes. Such multiple $U(1)$ magnetic fluxes stabilize the same number of the linear combination of the…
To establish metastable de Sitter vacua or even just scale-separated AdS, control over perturbative corrections to the string-derived leading-order 4d lagrangian is crucial. Such corrections can be classified in three types: First, there…
Within the class of inflationary models, k-inflation represents the most general single field framework that can be associated with an effective quadratic action for the curvature perturbations and a varying speed of sound. The incoming…
The end of inflation is connected to the standard cosmological scenario through reheating. During reheating, the inflaton oscillates around the minimum of the potential and thus decays into the daughter particles that populate the Universe…
We introduce a new class of models of chaotic inflation inspired by the superconformal approach to supergravity. This class of models allows a functional freedom of choice of the inflaton potential V = |f(\phi)|^2. The simplest model of…
This article represents the author's PhD thesis which is focused on moduli stabilisation in type IIB Calabi-Yau flux compactifications and its applications to cosmology. I derive the topological conditions on an arbitrary Calabi-Yau to give…
We revisit the two-stage procedure for moduli stabilization in Type IIB orientifolds at light K\"ahler-modulus limit. In view of the necessity to keep the K\"ahler geometry structure of the moduli space during the stabilization, we define a…
We consider the type II superstring compactified on Calabi-Yau threefolds at finite temperature. The latter is implemented at the string level by a free action on the Euclidean time circle. We show that all Kahler and complex structure…
Minimal chaotic models of D-term inflation predicts too large primordial tensor perturbations. Although it can be made consistent with observations utilizing higher order terms in the K\"ahler potential, expansion is not controlled in the…
The recent BICEP2 measurements of B-modes indicate a large tensor-to-scalar ratio in inflationary cosmology, which points towards trans-Planckian evolution of the inflaton. We propose possible string-theory realizations thereof. Schemes for…
We have investigated inflationary model constructed from minimally modified gravity (MMG) theories. The MMG theory in the form of $f({\bf H}) \propto {\bf H}^{1+p}$ gravity where, ${\bf H}$ is the Hamiltonian constraint in the Einstein…
Based on the flux-scaling scenario we study a model consisting on Type IIB string theory compactified on a Calabi-Yau manifold with a frozen complex structure in the presence of generic fluxes. The model contains (meta)stable Minkowski and…