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Related papers: Quintessential Inflation in Palatini Gravity

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We construct a model of quintessential inflation in Palatini $R^2$ gravity employing a scalar field with a simple exponential potential and coupled to gravity with a running non-minimal coupling. At early times, the field acts as the…

General Relativity and Quantum Cosmology · Physics 2022-11-03 Konstantinos Dimopoulos , Alexandros Karam , Samuel Sánchez López , Eemeli Tomberg

We have tested some simple quintessential inflation models, imposing that they match with the recent observational data provided by the BICEP and Planck's team and leading to a reheating temperature, which is obtained via gravitational…

General Relativity and Quantum Cosmology · Physics 2017-11-28 Llibert Aresté Saló , Jaume de Haro

An improved version of the well-known Peebles-Vilenkin model unifying early inflationary era to current cosmic acceleration, is introduced in order to match with the theoretical values of the spectral quantities provided by it with the…

General Relativity and Quantum Cosmology · Physics 2019-01-16 Jaume Haro , Weiqiang Yang , Supriya Pan

We study a model of quintessential inflation constructed in $R^2$ modified gravity with a non-minimally coupled scalar field, in the Palatini formalism. Our non-minimal inflaton field is characterised by a simple exponential potential. We…

General Relativity and Quantum Cosmology · Physics 2022-04-21 Konstantinos Dimopoulos , Alexandros Karam , Samuel Sánchez López , Eemeli Tomberg

We provide a detailed study of gravitational reheating in quintessential inflation generalizing previous analyses only available for the standard case when inflation is followed by an era dominated by the energy density of radiation.…

High Energy Physics - Phenomenology · Physics 2009-07-22 E. J. Chun , S. Scopel , I. Zaballa

Different well-know ways to reheat the universe such as instant preheating, the creation of particles nearly or conformally coupled with gravity, or from the decay products of a curvaton field, are revisited and discussed in detail in the…

General Relativity and Quantum Cosmology · Physics 2019-02-20 Jaume Haro

We compute numerically the reheating temperature due to the gravitational production of conformally coupled superheavy particles during the phase transition from the end of inflation to the beginning of kination in two different…

General Relativity and Quantum Cosmology · Physics 2023-01-03 Jaume de Haro , Llibert Aresté Saló

If the inflaton and the quintessence fields are identified, the background geometry evolves through a stiff epoch undershooting the expansion rate of a radiation-dominated plasma. For some classes of inflationary potentials this scenario is…

General Relativity and Quantum Cosmology · Physics 2020-01-08 Massimo Giovannini

We propose an idea to build a bridge between reheating and late-time observations in quintessential inflation by backtracking the evolution of the inflaton field from the present time to the end of reheating. This idea is implemented when…

High Energy Physics - Theory · Physics 2025-03-10 Ok Song An , Jin U Kang , Yong Jin Kim , Ui Ri Mun

Quintessential inflation describes a scenario in which both inflation and dark energy (quintessence) are described by the same scalar field. In conventional braneworld models of quintessential inflation gravitational particle production is…

High Energy Physics - Theory · Physics 2009-11-10 M. Sami , V. Sahni

We perform a numerical study of the preheating mechanism of particle production in models of quintessential inflation and compare it with the usual gravitational production mechanism. We find that even for a very small coupling between the…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. H. Campos , H. C. Reis , R. Rosenfeld

We investigate in detail a family of quintessential inflation models in the context of $R+R^2$ Palatini modified gravity. We find that successful inflation and quintessence are obtained with an inflaton scalar potential that is…

General Relativity and Quantum Cosmology · Physics 2021-02-26 Konstantinos Dimopoulos , Samuel Sánchez López

We compute numerically the reheating temperature due to the gravitational production of conformally coupled superheavy particles during the phase transition from the end of inflation to the beginning of kination in two different…

General Relativity and Quantum Cosmology · Physics 2021-11-10 Llibert Aresté Saló , Jaume de Haro

Palatini $F(R,X)$ gravity, with $X$ the inflaton kinetic term, proved to be a powerful framework for generating asymptotically flat inflaton potentials. Here we show that a quadratic Palatini $F(R,X)$ restores compatibility with the…

General Relativity and Quantum Cosmology · Physics 2025-11-18 Konstantinos Dimopoulos , Christian Dioguardi , Gert Hütsi , Antonio Racioppi

We study the consequences of reheating in quintessential inflation. From simple inflationary quintessential models introduced in cite{hap, hap2}, we show that when the reheating is due to the production of heavy massive particles…

General Relativity and Quantum Cosmology · Physics 2017-06-06 Jaume de Haro , Llibert Aresté Saló

Quintessential inflation is studied using a string modulus as the inflaton - quintessence field. The modulus begins its evolution at the steep part of its scalar potential, which is due to non-perturbative effects (e.g. gaugino…

High Energy Physics - Theory · Physics 2008-11-26 J. C. Bueno Sanchez , K. Dimopoulos

We propose a non-oscillatory no-scale supergravity model of inflation (NO-NO inflation) in which the inflaton does not oscillate at the end of the inflationary era. Instead, the Universe is then dominated by the inflaton kinetic energy…

High Energy Physics - Phenomenology · Physics 2021-03-31 John Ellis , Dimitri V. Nanopoulos , Keith A. Olive , Sarunas Verner

We study preheating in the Palatini formalism with a quadratic inflaton potential and an added $\alpha R^2$ term. In such models, the oscillating inflaton field repeatedly returns to the plateau of the Einstein frame potential, on which the…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-29 Alexandros Karam , Eemeli Tomberg , Hardi Veermäe

We study a new model of quintessential inflation which is inspired by supergravity and string theory. The model features a kinetic pole, which gives rise to the inflationary plateau, and a runaway quintessential tail. We envisage a coupling…

High Energy Physics - Phenomenology · Physics 2019-10-23 Konstantinos Dimopoulos , Mindaugas Karčiauskas , Charlotte Owen

One of the most important issues in an inflationary theory as standard or quintessential inflation is the mechanism to reheat the universe after the end of the inflationary period in order to match with the Hot Big Bang universe. In…

General Relativity and Quantum Cosmology · Physics 2023-01-03 Jaume Haro , Llibert Aresté Saló
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