Related papers: Naturalness and Chaotic Inflation in Supergravity …
The slow-roll inflation is a beautiful paradigm, yet the inflaton potential can hardly be sufficiently flat when unknown gravitational effects are taken into account. However, the hybrid inflation models constructed in D = 4 N = 1…
We go a step further in the search for a consistent and realistic supergravity model of large-field inflation by building a class of models with the following features: during slow-roll, all the scalar fields other than the inflaton are…
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 re-examine large scalar fields within effective field theory, in particular focussing on the issues raised by their use in inflationary models (as suggested by BICEP2 to obtain primordial tensor modes). We argue that when the large-field…
We construct a natural inflation model in supergravity where the inflaton is identified with a modulus field possessing a shift symmetry. The superpotential for the inflaton is generated by meson condensation due to strong dynamics with…
We address the problem of the large initial field values in chaotic inflation and propose a remedy in the framework of the so-called assisted inflation. We demonstrate that a 4-dimensional theory of multiple, scalar fields with initial…
Processes of particle production during inflation can increase the amplitude of the scalar metric perturbations. We show that such a mechanism can naturally arise in supergravity models where an axion-like field, whose potential is…
Hybrid inflation is a natural scenario in the absence of supersymmetry. In the context of supergravity, however, it has to face the naturalness problems of the initial conditions and of the adequate suppression of the inflaton mass. Both…
We investigate chaotic inflation models with two scalar fields, such that one field (the inflaton) rolls while the other is trapped in a false vacuum state. The false vacuum becomes unstable when the inflaton field falls below some critical…
The supergravity (SUGRA) theories with exact global $U(1)$ symmetry or shift symmetry in K\"ahler potential provide the natural frameworks for inflation. However, the quadratic inflation is disfavoured by the new results on primordial…
Supersymmetry is the most natural framework for physics above the TeV scale, and the corresponding framework for early-Universe cosmology, including inflation, is supergravity. No-scale supergravity emerges from generic string…
We consider "new inflation" inflationary models at small fields, embedded in minimal ${\cal N}=1$ supergravity with a single chiral superfield. Imposing a period of inflation compatible with experiment severely restricts possible models,…
We construct a hybrid inflationary model associated with the superheavy scale of the minimal supersymmetric standard model which is based on the simplest superpotential for symmetry breaking and in which the inflaton potential along the…
In this talk we propose a natural double inflation model in supergravity. Chaotic inflation first takes place by virtue of the Nambu-Goldstone-like shift symmetry. During chaotic inflation, an initial value of second inflation (new…
In this paper we show that the new approach to the embedding of the inflationary potentials into supergravity, presented in a quite recent paper [11] of Ferrara, Kallosh, Linde and Porrati can be formulated within the framework of standard…
We focus on the massive gauge theory formulation of axion monodromy inflation. We argue that a gauge symmetry hidden in these models is the key protection mechanism from dangerous corrections from both field theory and gravitational…
We show that models of chaotic inflation based on the phi^p potential and a linear non-minimal coupling to gravity, fR=1+cR phi, can be done consistent with data in the context of Supergravity, retaining the perturbative unitarity up to the…
We generalize the embedding of induced-gravity inflation beyond the no-scale Supergravity presented in arXiv:1403.5486 employing two gauge singlet chiral superfields, a superpotential uniquely determined by applying a continuous R and a…
We consider an initial condition problem in a nearly quadratic chaotic inflation model in supergravity. We introduce shift symmetry breaking not only in the superpotential but also in the Kahler potential. In this model the inflaton…
Recently it was shown that discrete R-invariance in superpotential can lead to a successful flat potential in inflation. We suggest that this discrete R-symmetry arises from an underlying supersymmetric gauge theory, which gives rise to a…