English
Related papers

Related papers: On Friedmann-Lema\^{\i}tre-Robertson-Walker cosmol…

200 papers

We consider FRW cosmology in non-local modified gravity. Its local scalar-tensor formulation is developed. It is explicitly demonstrated that such theory may lead to the unification of early-time inflation with late-time cosmic…

High Energy Physics - Theory · Physics 2008-11-26 Shin'ichi Nojiri , Sergei D. Odintsov

We study FRW cosmology for a non-linear modified F(R) Horava-Lifshitz gravity which has a viable convenient counterpart. A unified description of early-time inflation and late-time acceleration is possible in this theory, but the…

High Energy Physics - Theory · Physics 2011-02-09 E. Elizalde , S. Nojiri , S. D. Odintsov , D. Saez-Gomez

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

At the present work, it is studied the extension of F (R) gravities to the new recently proposed theory of gravity, the so-called Horava-Lifshitz gravity, which provides a way to make the theory power counting renormalizable by breaking…

General Relativity and Quantum Cosmology · Physics 2015-05-20 Diego Sáez-Gómez

The actual accelerated expansion of the universe continues being a mystery in physics. Some models had been proposed for this explanations, among them the dark energy, which however has problems of experimental character as well as…

General Relativity and Quantum Cosmology · Physics 2012-11-13 Alejandro Guarnizo

We review the accelerating (mainly, dark energy) cosmologies in modified gravity. Special attention is paid to cosmologies leading to finite-time future singularities in $F(R)$, $F(G)$ and $\mathcal{F}(R,G)$ modified gravities. The removal…

General Relativity and Quantum Cosmology · Physics 2013-02-21 Kazuharu Bamba , Shin'ichi Nojiri , Sergei D. Odintsov

There are so many ideas that potentially explain the dark energy phenomenon, current research is focusing on a more in-depth analysis of the potential effects of modified gravity on both local and cosmic scales. In this paper we have…

General Relativity and Quantum Cosmology · Physics 2025-11-24 S. H. Shekh , Hira Sohail , Irfan Mahmood , Allah Ditta , Anil Kumar Yadav

It is accepted by the majority of scientific community that the Universe is currently in an accelerated epoch. In order to explain this shock of late 90's, a lot of dark energy candidates have been proposed. We study in the context of f (R)…

High Energy Physics - Theory · Physics 2014-11-20 Diego Sáez-Gómez

We develop the reconstruction program for the number of modified gravities: scalar-tensor theory, $f(R)$, $F(G)$ and string-inspired, scalar-Gauss-Bonnet gravity. The known (classical) universe expansion history is used for the explicit and…

High Energy Physics - Theory · Physics 2010-04-06 Shin'ichi Nojiri , Sergei D. Odintsov

Classical generalization of general relativity is considered as gravitational alternative for unified description of the early-time inflation with late-time cosmic acceleration. The structure and cosmological properties of number of…

General Relativity and Quantum Cosmology · Physics 2011-07-26 Shin'ichi Nojiri , Sergei D. Odintsov

A viable radiation dominated era in the early universe is best described by the standard (FLRW) model of cosmology. In this short review, we demonstrate reconstruction of the forms of F(R) in the modified theory of gravity and the metric…

General Relativity and Quantum Cosmology · Physics 2024-01-23 Dalia Saha , Manas Chakrabortty , Abhik Kumar Sanyal

This thesis explores the cosmological implications of modified gravity, focusing on nonmetricity-based $f(Q)$ gravity as an alternative to the $\Lambda$CDM model in explaining cosmic acceleration. Chapter I lays the theoretical groundwork…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Gaurav N. Gadbail

In this paper we investigate the accelerating and decelerating cosmological models with non-linear spinor fields and non-minimal interaction of $f(R)$ gravity with a scalar field. We combine two different approaches to the description of…

General Relativity and Quantum Cosmology · Physics 2013-12-12 Yu. A. Rybalov , A. N. Makarenko , K. E. Osetrin

We study scalar-tensor theory, k-essence and modified gravity with Lagrange multiplier constraint which role is to reduce the number of degrees of freedom. Dark Energy cosmology of different types ($\Lambda$CDM, unified inflation with DE,…

High Energy Physics - Theory · Physics 2010-12-09 Salvatore Capozziello , Jiro Matsumoto , Shin'ichi Nojiri , Sergei D. Odintsov

One of the greatest challenges in cosmology today is to determine the nature of dark energy, the sourse of the observed present acceleration of the Universe. Besides the vacuum energy, various dark energy models have been suggested. The…

We examine the cosmological dynamics of Einstein-Gauss-Bonnet gravity models in a four-dimensional spatially flat FLRW metric. These models are described by $f\left( R,\mathcal{G}\right) =f\left( R+\mu \mathcal{G}\right) $ theory of…

General Relativity and Quantum Cosmology · Physics 2025-12-10 Nikolaos Dimakis , Alex Giacomini , Genly Leon , Andronikos Paliathanasis , Ekaterina Pozdeeva , Sergey Vernov

The cosmological reconstruction scheme for modified $F(R)$ gravity is developed in terms of e-folding (or, redshift). It is demonstrated how any FRW cosmology may emerge from specific $F(R)$ theory. The specific examples of well-known…

High Energy Physics - Theory · Physics 2014-11-20 Shin'ichi Nojiri , Sergei D. Odintsov , Diego Saez-Gomez

This thesis investigates late-time cosmic acceleration using modified gravity theories with a focus on $f(Q)$ gravity, as an alternative to the $\Lambda$CDM model. The standard cosmological model attributes the acceleration to a…

General Relativity and Quantum Cosmology · Physics 2025-12-18 S. A. Narawade

We study cosmologies in modified theories of gravity considering Lagrangian density $f(R)$ which is a polynomial function of scalar curvature ($R$) in the Einstein-Hilbert action in vacuum. The field equation obtained from the modified…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-29 B. C. Paul , P. S. Debnath , S. Ghose

We review modified $F(R)$ gravity as realistic candidate to describe the observable universe expansion history. We show that recent cosmic acceleration, radiation/matter-dominated epoch and inflation could be realized in the framework of…

High Energy Physics - Theory · Physics 2008-07-08 Shin'ichi Nojiri , Sergei D. Odintsov
‹ Prev 1 2 3 10 Next ›