Related papers: Hillclimbing inflation
This article presents a possible inflation scenario as a consequence of non-minimal gravitational couplings in the Conformal Standard Model. The model consists, in comparison to the SM, of additional right-chiral neutrinos and complex…
We study a scalar field with non-minimal kinetic coupling to itself and to the curvature. The slow rolling conditions allowing an inflationary background have been found. The quadratic and Higgs type potentials have been considered, and the…
In the framework of gravitational models obtained from the Geometric Inflation's proposal, where an infinite tower of curvature scalars are included into the action, we compute the slow-roll parameters by the Hubble slow-roll approach. We…
In this PhD thesis, we investigate generic features of inflation which are strictly related to fundamental aspects of UV-physics scenarios, such as string theory or supergravity. After a short introduction to standard and inflationary…
We investigate the dynamics of the recently proposed model of assisted inflation. In this model an arbitrary number of scalar fields with exponential potentials evolve towards an inflationary scaling solution, even if each of the individual…
In this work, we study constant-roll inflation driven by a scalar field with non-minimal derivative coupling to gravity, via the Einstein tensor. This model contains a free parameter, $\eta$, which quantifies the non-minimal derivative…
We explore in the supergravity context the possibility that a Higgs scalar may drive inflation via a non-minimal coupling to gravity characterised by a large dimensionless coupling constant. We find that this scenario is not compatible with…
Models of cosmic inflation suggest that our universe underwent an early phase of accelerated expansion, driven by the dynamics of one or more scalar fields. Inflationary models make specific, quantitative predictions for several observable…
We investigate models in which the inflaton emerges as a composite field of a four dimensional, strongly interacting and nonsupersymmetric gauge theory featuring purely fermionic matter. We show that it is possible to obtain successful…
We consider a modified gravity framework for inflation by adding to the Einstein-Hilbert action a direct $f(\phi)T$ term, where $\phi$ is identified as the inflaton and $T$ is the trace of the energy-momentum tensor. The framework goes to…
We consider the torsional completion of gravity with spinor and scalar fields: we show how in this environment conditions of extreme symmetry or specific approximations imply the scalar field to be constant, so that slow-roll takes place…
Inflationary cosmology proposes that the early Universe undergoes accelerated expansion, driven, in simple scenarios, by a single scalar field, or inflaton. The form of the inflaton potential determines the initial spectra of density…
Inflection point inflation generically includes a deviation from slow-roll when the inflaton approaches the inflection point. Such deviations are shown to be generated by transitions between singular trajectories. The effects on the power…
In string-inspired supergravity theory, K\"{a}hler metric of chiral matter fields often has a pole. Such K\"{a}hler metric is interesting from the viewpoint of the framework of the pole inflation, where the scalar potential can be stretched…
Reasonable-looking models of inflation are compared, taking into account the possibility that the curvature perturbation might originate from some "curvaton" field different from the inflaton.
We investigate the predictions of inflation models with a non-minimal coupling to gravity for inflationary observables such as the spectral index and tensor-to-scalar ratio in a general setting. We argue that, depending on the relation…
Within the framework of geometric inflation, where the Friedmann equation is modified to incorporate an infinite series of higher curvature corrections, we describe the emergence of a de Sitter inflationary phase near the poles of an…
We realize and study a model of hybrid inflation in the context of softly broken supersymmetry. The inflaton is taken to be a flat direction in the superfield space and, due to unsuppressed couplings, its soft supersymmetry breaking mass…
We consider two classes of non-minimally coupled inflation models; those with a quadratic coupling of the inflaton to gravity, and the `Universal Attractor' models where the coupling is connected to the potential. We make a detailed…
We argue, using a phenomenological holographic approach, that walking, strongly coupled gauge theories generate a suitable potential for a small field inflation model. We show that the effective description is a model of a single inflaton.…