Related papers: Perturbative K\"ahler Moduli Inflation
In this talk I discuss recent developments in moduli stabilisation, SUSY breaking and chiral D-brane models together with several interesting features of cosmological models built in the framework of type IIB string compactifications. I…
We discuss the hybrid inflation model where the inflaton field is nonminimally coupled to gravity. In the Jordan frame, the potential contains $\phi^4$ term as well as terms in the original hybrid inflation model. In our model, inflation…
We investigate the embedding of brane anti-brane inflation into a concrete type IIB string theory compactification with all moduli fixed. Specifically, we are considering a D3-brane, whose position represents the inflaton $\phi$, in a…
We review the main aspects of the warm inflation scenario, focusing on the inflationary dynamics and the predictions related to the primordial spectrum of perturbations, to be compared with the recent cosmological observations. We study in…
The single scalar field inflationary models that lead to scalar and tensor perturbation spectra with amplitudes varying in direct proportion to one another are reconstructed by solving the Stewart-Lyth inverse problem to next-to-leading…
We consider the Type IIB string theory in the presence of various extra $7/\bar 7$-brane pairs compactified on a warped Calabi-Yau threefold that admits a conifold singularity. We demonstrate that the volume modulus can be stabilized…
Generalized slow roll conditions and parameters are obtained for a general form of scalar-tensor theory (with no external sources), having arbitrary functions describing a nonminimal gravitational coupling F(\phi), a Kahler-like kinetic…
We have recently proposed attractor models for modulus fixing, inflation, supersymmetry breaking and dark energy based on no-scale supergravity. In this paper we develop phenomenological and cosmological aspects of these no-scale attractor…
We obtain cosmological constraints on models of inflation which exhibit rapid roll solutions. Rapid roll attractors exist for potentials with large mass terms and are thus of interest for inflationary model building within string theory. We…
One method to reconstruct the scalar field potential of inflation is a perturbative approach, where the values of the potential and its derivatives are calculated as an expansion in departures from the slow-roll approximation. They can then…
We calculate power spectra of cosmological perturbations at high accuracy for two classes of inflation models. We classify the models according to the behaviour of the Hubble distance during inflation. Our approximation works if the Hubble…
We study the $D$-term inflation scenario with a nonperturbative K\"ahler potential of the dilaton field. Although the FI term which leads an inflationary expansion is given by the derivative of the K\"ahler potential with respect to the…
We investigate models of `intermediate' inflation, where the scale factor $a(t)$ grows as $a(t) = \exp (A t^f)$, $0 < f < 1$, $A$ constant. These solutions arise as exact analytic solutions for a given class of potentials for the inflaton…
Slow roll reconstruction is derived from the Hamilton-Jacobi formulation of inflationary dynamics. It automatically includes information from sub-leading terms in slow roll, and facilitatesthe inclusion of priors based on the duration on…
It is tempting to inflate along one of the many flat directions that arise in supersymmetric theories. The required flatness of the potential to obtain sufficient inflation and to not overproduce density fluctuations occurs naturally.…
We formalize the Hubble slow-roll formalism for inflationary dynamics in Randall-Sundrum Type II braneworld cosmologies, defining Hubble slow-roll parameters which can be used along with the Hamilton-Jacobi formalism. Focussing on the…
We study inflation in scalar-tensor perturbative quantum gravity driven by a one-loop effective potential. We consider effective potentials generated by three models. The first model describes a single scalar field with a non-vanishing…
We review two types of fractional Kaehler potentials $K$ which reduce, along the inflationary path, to the form $N/(1-\phi^{q_{\rm M}})^{p}$ with $q_{\rm M}=1$ or $2$ and $0.1\leq p\leq10$. Their coexistence, within a non-linear sigma…
We study the large volume limit of the scalar potential in Calabi-Yau flux compactifications of type IIB string theory. Under general circumstances there exists a limit in which the potential approaches zero from below, with an associated…
We describe a broad class of multi-field inflationary models with spontaneously broken conformal invariance. It generalizes the recently discovered class of cosmological attractors with a single inflaton field. In the new multi-field…