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Related papers: Quintessential Inflation in Palatini Gravity

200 papers

In this talk recent developments of the theory of preheating after inflation are briefly reviewed. In inflationary cosmology, the particles constituting the Universe are created after inflation due to their interaction with moving inflaton…

High Energy Physics - Phenomenology · Physics 2009-10-31 Lev Kofman

We consider a non-standard generalized model of gravity coupled to a neutral scalar "inflaton" as well as to the fields of the electroweak bosonic sector. The essential new ingredient is employing two alternative non-Riemannian space-time…

General Relativity and Quantum Cosmology · Physics 2017-09-18 Eduardo Guendelman , Emil Nissimov , Svetlana Pacheva

The curvaton reheating in a tachyonic braneworld inflationary universe model with an exponential potential is studied. We have found that the energy density in the kinetic epoch, has a complicated dependencies of the scale factor. For…

High Energy Physics - Theory · Physics 2009-11-11 Cuauhtemoc Campuzano , Sergio del Campo , Ramon Herrera

In this paper, we study the post-inflationary era called reheating stage. For this purpose, we consider a model in which the inflaton is non-minimally coupled to the curvature within the hybrid metric-Palatini approach. Furthermore, to…

General Relativity and Quantum Cosmology · Physics 2024-05-28 Brahim Asfour , Aatifa Bargach , Yahya Ladghami , Ahmed Errahmani , Taoufik Ouali

A generic feature of cosmic quintessence models is the possibility of significant energy density in the scalar field during the radiation dominated epoch. This possibility is even greater if the quintessence field begins in a…

Astrophysics · Physics 2007-05-23 G. J. Mathews , K. Ichiki , T. Kajino , M. Orito , M. Yahiro

We investigate warm inflation in the framework of $f(Q)$ gravity within a Friedmann-Robertson-Walker spacetime. Unlike cold inflation, where the inflaton evolves in isolation, warm inflation features continuous interaction between the…

General Relativity and Quantum Cosmology · Physics 2026-05-29 Tuhina Ghorui , Prabir Rudra , Farook Rahaman , Behnam Pourhassan

It is assumed that during inflation, all energy was contained in a slow-rolling inflaton field $\phi$. The particles constituting the Universe are created due to interactions with the field $\phi$ coherently oscillating after inflation. The…

High Energy Physics - Phenomenology · Physics 2007-05-23 Lev Kofman

This thesis compiles the results of six works which deal with - inflationary model building and estimation of cosmological parameters from various field theoretic setup, quantification of reheating temperature, studies of leptogenesis in…

High Energy Physics - Theory · Physics 2016-04-12 Sayantan Choudhury

We investigate gravitational reheating in the Starobinsky model in the Jordan frame, where inflation is driven by an $R^2$ modification of gravity with no explicit inflaton field. In this description, reheating proceeds exclusively through…

General Relativity and Quantum Cosmology · Physics 2026-03-06 Gláuber C. Dorsch , Luiz Carlos Miranda , Nelson Yokomizo

We consider the constraints that can be imposed on a wide class of Inflation models in modified gravity scenarios in which the Friedmann equation is modified by the inclusion of $\rho^2$ terms, where $\rho$ is the total energy density. In…

High Energy Physics - Phenomenology · Physics 2009-11-11 Edmund J. Copeland , Osamu Seto

In this paper, we employ the Palatini formalism to investigate the dynamics of large-field inflation using a renormalizable polynomial inflaton potential in the context of $f(R,\phi)$ gravity. Assuming instant reheating, we make a…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-20 Nilay Bostan , Canan Karahan , Ozan Sargın

We show that upon applying Palatini $f(R)$, characterized by an $\a R^2$-term, within a scenario motivated by a temporal variation of strong coupling constant, then one gets a quadratic kinetic energy. We do not drop this term, but rather…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-15 M. AlHallak , A. AlRakik , N. Chamoun , M. S. El-Daher

We study in detail a new model of quintessential inflation where the inflaton field is coupled to the Gauss-Bonnet term. This coupling ensures that the variation of the field is kept sub-Planckian, which avoids the 5th force problem as well…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-24 Carsten van de Bruck , Konstantinos Dimopoulos , Chris Longden , Charlotte Owen

At the end of inflation, the inflaton field decays into an initially nonthermal population of relativistic particles which eventually thermalize. We consider the production of dark matter from this relativistic plasma, focusing on the…

High Energy Physics - Phenomenology · Physics 2018-12-18 Marcos A. G. Garcia , Mustafa A. Amin

We discuss a model in which high energy brane corrections allow a single scalar field to describe inflation at early epochs and quintessence at late times. The reheating mechanism in the model originates from Born-Infeld matter whose energy…

High Energy Physics - Theory · Physics 2009-11-10 M. Sami , N. Dadhich , Tetsuya Shiromizu

The gravitational production of superheavy dark matter is studied in the context of quintessential inflation. The superheavy particles, whose decay products are baryonic matter and are the responsible for the reheating of the universe after…

General Relativity and Quantum Cosmology · Physics 2019-08-21 Jaume Haro , Llibert Aresté Saló

Reheating after inflation occurs due to particle production by the oscillating inflaton field. In this paper we describe the perturbative approach to reheating, and then concentrate on effects beyond the perturbation theory. They are…

High Energy Physics - Phenomenology · Physics 2009-09-29 Lev Kofman , Andrei Linde , Alexei Starobinsky

In this article we calculate the reheating temperature in the cosmological scenarios where heavy scalar particles are gravitationally produced, due to a conformally coupled interaction between a massive scalar quantum field and the Ricci…

General Relativity and Quantum Cosmology · Physics 2024-11-05 Jaume de Haro , Llibert Aresté Saló , Supriya Pan

In this work, we study a new quintessence model associated with non-Abelian gauge fields, minimally coupled to Einstein gravity. This gauge theory has been recently introduced and studied as an inflationary model, called gauge-flation.…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-03 A. Mehrabi , A. Maleknejad , V. Kamali

We consider the abundance of gravitinos created from the vacuum fluctuation, in a class of `new' inflation models for which global supersymmetry is a good approximation. Immediately after inflation, gravitinos are produced, with number…

High Energy Physics - Phenomenology · Physics 2009-10-31 David H Lyth