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Related papers: Cosmology in nonlocal gravity

200 papers

A unified description of early-time inflation with the current cosmic acceleration is achieved by means of a new theory that uses a quadratic model of gravity, with the inclusion of an exponential $F(R)$-gravity contribution for dark…

General Relativity and Quantum Cosmology · Physics 2017-06-28 E. Elizalde , S. D. Odintsov , L. Sebastiani , R. Myrzakulov

We propose a model for cosmic inflation which is based on an effective description of strongly interacting, nonsupersymmetric matter within the framework of dynamical Abelian projection and centerization. The underlying gauge symmetry is…

High Energy Physics - Phenomenology · Physics 2009-11-07 Ralf Hofmann , Mathias Th. Keil

A classical nonlocal generalization of Einstein's theory of gravitation has recently been developed via the introduction of a scalar causal "constitutive" kernel that must ultimately be determined from observational data. It turns out that…

Astrophysics of Galaxies · Physics 2014-05-14 S. Rahvar , B. Mashhoon

We develop a theory of nonlinear cosmological perturbations on superhorizon scales where a characteristic length scale of perturbations is longer than the Hubble radius, in general theoretical frameworks. Our formalism is based on the…

General Relativity and Quantum Cosmology · Physics 2018-04-24 Yu-ichi Takamizu

We propose a novel modified gravity: unimodular generalization of the Born-Infeld-$f(R)$ gravity within the framework of cosmology. After formulating the action corresponding to the generalized Born-Infeld-$f(R)$ gravity, we present a…

General Relativity and Quantum Cosmology · Physics 2024-02-16 Salih Kibaroğlu , Sergei D. Odintsov , Tanmoy Paul

Even if the fundamental action of gravity is local, the corresponding quantum effective action, that includes the effect of quantum fluctuations, is a nonlocal object. These nonlocalities are well understood in the ultraviolet regime but…

High Energy Physics - Theory · Physics 2018-03-21 Enis Belgacem , Yves Dirian , Stefano Foffa , Michele Maggiore

In this paper we investigate the inflationary dynamics of an $f(R)$ gravity in the presence of a canonical scalar field. We specifically choose the cosmological evolution to be a quasi-de Sitter evolution and also the $f(R)$ gravity is…

General Relativity and Quantum Cosmology · Physics 2018-08-01 K. Kleidis , V. K. Oikonomou

A period of rapidly accelerating expansion is expected in the early Universe implemented by a scalar field slowly rolling down along an asymptotically flat potential preferred by the current data. In this paper, we point out that this…

General Relativity and Quantum Cosmology · Physics 2022-09-01 Rong-Gen Cai , Yu-Shi Hao , Shao-Jiang Wang

We consider modified gravity which may describe the early-time inflation and/or late-time cosmic acceleration of the universe. In particular, we discuss the properties of $F(R)$, $F(G)$, string-inspired and scalar-Einstein-Gauss-Bonnet…

General Relativity and Quantum Cosmology · Physics 2013-06-20 Shin'Ichi Nojiri , Sergei D. Odintsov

The incorporation of bulk viscosity process to General Relativity leads to the appearance of nonsingular backgrounds that, at early and late times, depict an accelerated universe. These backgrounds could be analytically calculated and…

General Relativity and Quantum Cosmology · Physics 2017-12-20 Jaume Haro , Supriya Pan

WE analyse the universe inflation when the source of gravity is electromagnetic fields obeying nonlinear electrodynamics with two parameters and without singularities. The cosmology of the universe with stochastic magnetic fields is…

General Physics · Physics 2024-03-27 S. I. Kruglov

We present an introduction to cosmic inflation in the framework of Palatini gravity, which provides an intriguing alternative to the conventional metric formulation of gravity. In the latter, only the metric specifies the spacetime…

General Relativity and Quantum Cosmology · Physics 2025-01-23 Ioannis D. Gialamas , Alexandros Karam , Thomas D. Pappas , Eemeli Tomberg

In this talk, I present a theory of quantum gravity beyond Einstein. The theory is established based on spinnic and scaling gauge symmetries by treating the gravitational force on the same footing as the electroweak and strong forces. A…

High Energy Physics - Theory · Physics 2015-11-04 Yue-Liang Wu

A brief account of the present status of the recent nonlocal generalization of Einstein's theory of gravitation is presented. The main physical assumptions that underlie this theory are described. We clarify the physical meaning and…

General Relativity and Quantum Cosmology · Physics 2015-01-20 B. Mashhoon

In the present work we derive an exact solution of an isotropic and homogeneous Universe governed by $f(T)$ gravity. We show how the torsion contribution to the FRW cosmology can provide a \textit{unique} origin for both early and late…

General Relativity and Quantum Cosmology · Physics 2016-10-19 G. G. L. Nashed , W. El Hanafy

Scalar-tensor theories of gravity that embrace conformal coupling to the scalar curvature are the focal point of cosmology on discussions of inflation and late-time accelerating universe. Although there exists a stringent nucleo-synthesis…

General Relativity and Quantum Cosmology · Physics 2022-04-26 M. Yoshimura

In this work, we analyzed the improved Deser-Woodard non-local gravity over the background of five different bouncing cosmologies, whose premise is avoid the initial singular state of the universe. We developed the numerical solution for…

General Relativity and Quantum Cosmology · Physics 2022-06-01 D. Jackson , R. Bufalo

In view to scrutinize the idea that nonlocal modifications of General Relativity could dynamically address the dark energy problem, we investigate the evolution of the Universe at infrared scales as an Infinite Derivative Gravity model of…

General Relativity and Quantum Cosmology · Physics 2024-05-03 Salvatore Capozziello , Anupam Mazumdar , Giuseppe Meluccio

We extend the thermodynamic derivation of gravity in the Jacobson framework by generalizing the Clausius relation through a nontrivial entropy functional. We show that entropy deformations appear as modifications of the effective…

General Relativity and Quantum Cosmology · Physics 2026-04-14 H. R. Fazlollahi

The generalized kinetic term of a dilaton gives the classical superinflation without recourse to any potential, and the quantum version of the dilaton gravity exhibits the finite curvature and graceful exit. For $p=2$ case, the model…

High Energy Physics - Theory · Physics 2008-02-03 Won T. Kim , Myungseok Yoon
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