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Related papers: Nonminimal coupling and inflationary attractors

200 papers

We study multifield inflation in scenarios where the fields are coupled non-minimally to gravity via $\xi_I(\phi^I)^n g^{\mu\nu}R_{\mu\nu}$, where $\xi_I$ are coupling constants, $\phi^I$ the fields driving inflation, $g_{\mu\nu}$ the…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-29 Pedro Carrilho , David Mulryne , John Ronayne , Tommi Tenkanen

With a scalar field non-minimally coupled to curvature, the underlying geometry and variational principle of gravity - metric or Palatini - becomes important and makes a difference, as the field dynamics and observational predictions…

General Relativity and Quantum Cosmology · Physics 2020-08-26 Laur Järv , Alexandros Karam , Aleksander Kozak , Angelos Lykkas , Antonio Racioppi , Margus Saal

We compute in detail how deviations from Einstein gravity at the inflation energy scale could appear as non-Gaussian features in the sky. To illustrate this we use multi-field $\alpha-$attractor models in the framework of supergravity to…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-14 Nicola Bartolo , Domenico Matteo Bianco , Raul Jimenez , Sabino Matarrese , Licia Verde

In this study, we investigate swampland conjectures within the setup of matter and non-metricity nonminimal coupling theories of gravity. We examine how the inflationary solution produced by a single scalar field can be resolved with the…

General Relativity and Quantum Cosmology · Physics 2024-01-01 Sanjay Mandal , Kazuharu Bamba

We show that if the inflaton has a non-minimal coupling to gravity and the Planck scale is dynamically generated, the results of Coleman-Weinberg inflation are confined in between two attractor solutions: quadratic inflation, which is ruled…

High Energy Physics - Phenomenology · Physics 2016-01-18 Kristjan Kannike , Antonio Racioppi , Martti Raidal

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.…

High Energy Physics - Theory · Physics 2012-08-16 Nick Evans , James French , Keun-Young Kim

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…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-10 David I. Kaiser

Motivated by $\alpha$-attractor models, in this paper we consider a Gauss-Bonnet inflation with E-model type of potential. We consider the Gauss-Bonnet coupling function to be the same as the E-model potential. In the small $\alpha$ limit…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-02 Kourosh Nozari , Narges Rashidi

Inflationary $\alpha$-attractor models can be naturally implemented in supergravity with hyperbolic geometry. They have stable predictions for observables, such as $n_s=1-{2/ N_e} $, assuming that the potential in terms of the original…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-20 Renata Kallosh , Andrei Linde

We construct the global phase portraits of inflationary dynamics in teleparallel gravity models with a scalar field nonminimally coupled to torsion scalar. The adopted set of variables can clearly distinguish between different asymptotic…

General Relativity and Quantum Cosmology · Physics 2022-03-03 Laur Järv , Joosep Lember

We investigate the possibility that the inflaton, in particular in conformal inflation models, is also a chameleon, i.e. that it couples to the energy density of some heavy non-relativistic matter present during inflation. We find new and…

High Energy Physics - Theory · Physics 2019-04-24 Heliudson Bernardo , Renato Costa , Horatiu Nastase , Amanda Weltman

We study an inflation mechanism based on attractor properties in cosmological evolutions of a spatially flat Friedmann-Robertson-Walker spacetime based on the Einstein-scalar field theory. We find a new way to get the Hamilton-Jacobi…

General Relativity and Quantum Cosmology · Physics 2013-12-10 Hyeong-Chan Kim

We examine inflationary models in the $f(R, T)$ gravity framework where we have a conformal constant and an $RT$-mixing term apart from an R term. The RT-mixing term introduces non-minimal coupling between gravity and matter. We consider…

General Relativity and Quantum Cosmology · Physics 2025-04-16 Sohan Kumar Jha , Anisur Rahaman

We investigate models in which inflation is driven by an ultraviolet safe and interacting scalar sector stemming from a new class of nonsupersymmetric gauge field theories. These new theories, differently from generic scalar models, are…

High Energy Physics - Phenomenology · Physics 2015-05-22 Niklas Grønlund Nielsen , Francesco Sannino , Ole Svendsen

We demonstrate that the latest constraints on inflationary observables, namely the tensor-to-scalar ratio $r$ and the scalar spectral index $n_{_S}$, from the Cosmic Background Radiation (CMB) observations are already strong enough to rule…

General Relativity and Quantum Cosmology · Physics 2022-12-07 N. Avdeev , A. Toporensky

Inflationary slow-roll dynamics in Einstein gravity with a non-minimal scalar-curvature coupling can be equivalent to that in the certain f(R) gravity theory. We review the correspondence and extend it to N=1 supergravity. The non-minimal…

High Energy Physics - Theory · Physics 2015-06-04 Sergei V. Ketov , Alexei A. Starobinsky

We discuss, in the context of alternative theories of gravity with nonminimal coupling between matter and curvature, if inflationary solutions driven by a single scalar field can be reconciled with the swampland conjectures about the…

General Relativity and Quantum Cosmology · Physics 2023-04-19 Orfeu Bertolami , Cláudio Gomes , Paulo M. Sá

We investigate a class of inflationary models in modified gravity theories which contain a non-minimal coupling between gravity and a scalar field $\phi$ (inflaton) as $f(R,T)=R \bigl(1+\alpha+ \kappa^4 \beta T \bigr)+\kappa^2\gamma T $…

General Relativity and Quantum Cosmology · Physics 2024-12-03 Payel Sarkar , Ashmita , Prasanta Kumar Das

In this paper, we explore a novel observational signature of gravitational corrections during slow-roll inflation. We study the coupling of the inflaton field to higher-curvature tensors in models with a minimal breaking of conformal…

High Energy Physics - Theory · Physics 2016-02-17 Daniel Baumann , Hayden Lee , Guilherme L. Pimentel

We study a supergravity model of inflation essentially depending on one parameter which can be identified with the slope of the potential at the origin. In this type of models the inflaton rolls at high energy from negative values and a…

Astrophysics · Physics 2009-11-10 G. German , A. de la Macorra