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Related papers: Formalizing Anisotropic Inflation in Modified Grav…

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We systematically review some standard issues and also the latest developments of modified gravity in cosmology, emphasizing on inflation, bouncing cosmology and late-time acceleration era. Particularly, we present the formalism of standard…

General Relativity and Quantum Cosmology · Physics 2021-05-25 S. Nojiri , S. D. Odintsov , V. K. Oikonomou

In this paper, we investigate anisotropic cosmological solutions within the framework of Born-Infeld-f(R) gravity, a modification of general relativity that incorporates higher-order curvature invariants. Specifically, we focus on the…

General Relativity and Quantum Cosmology · Physics 2025-01-06 Salih Kibaroğlu

We study the future evolution of quintessence/phantom dominated epoch in modified $F(R)$-gravity which unifies the early-time inflation with late-time acceleration and which is consistent with observational tests. Using the reconstruction…

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

We study the quantum evolution of the early universe, its semi-classical analogue together with inflationary regime, in view of a generalized modified theory of gravity. The action is built by supplementing the non-minimally coupled…

High Energy Physics - Theory · Physics 2021-01-11 Ranajit Mandal , Dalia Saha , Mohosin Alam , Abhik Kumar Sanyal

Viable models of modified gravity which satisfy both local as well as cosmological tests are investigated. It is demonstrated that some versions of such highly non-linear models exhibit multiply de Sitter universe solutions, which often…

General Relativity and Quantum Cosmology · Physics 2009-02-20 G. Cognola , E. Elizalde , S. D. Odintsov , P. Tretyakov , S. Zerbini

We explore conformal-anomaly driven inflation in $F(R)$ gravity without invoking the scalar-tensor representation. We derive the stress-energy tensor of the quantum anomaly in the flat homogeneous and isotropic universe. We investigate a…

High Energy Physics - Theory · Physics 2014-08-13 Kazuharu Bamba , R. Myrzakulov , S. D. Odintsov , L. Sebastiani

In this paper, we discuss inflationary scenario via scalar field and fluid cosmology for anisotropic homogeneous universe model in $f(R)$ gravity. We consider an equation of state which corresponds to quasi-de Sitter expansion and…

General Relativity and Quantum Cosmology · Physics 2018-04-11 M. Sharif , Iqra Nawazish

With the non-metricity scalar $Q$ as the functional argument, several $f(Q)$ gravity models are found to be proposed which are perfectly able to mimic the late-time accelerated expansion as pointed out by the type Ia supernovae…

General Relativity and Quantum Cosmology · Physics 2026-02-03 Subhajit Pal , Atanu Mukherjee , Ritabrata Biswas , Farook Rahaman

Using the fluid representation, we formulate the conditions for the appearance of all four types finite-time future singularity in modified gravity in accelerating FRW universe. It stressed that number of standard quintessence/phantom DE…

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

A class of exact, anisotropic cosmological solutions to the vacuum Brans-Dicke theory of gravity is considered within the context of the pre-big bang scenario. Included in this class are the Bianchi type III, V and VI_h models and the…

General Relativity and Quantum Cosmology · Physics 2016-08-31 D. Clancy , J. E. Lidsey , R. Tavakol

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

We consider the non-minimal model of gravity in $Y(R) F^2$-form. We investigate a particular case of the model, for which the higher order derivatives are eliminated but the scalar curvature $R$ is kept to be dynamical via the constraint…

General Relativity and Quantum Cosmology · Physics 2017-11-17 Muzaffer Adak , Ozgur Akarsu , Tekin Dereli , Ozcan Sert

We use a dynamical systems approach to investigate Bianchi type I and II universes in quadratic theories of gravity. Due to the complicated nature of the equations of motion we focus on the stability of exact solutions and find that there…

General Relativity and Quantum Cosmology · Physics 2008-11-26 John D. Barrow , Sigbjorn Hervik

This thesis explores the late-time cosmic acceleration within the framework of $f(R,T)$ gravity, a general relativity modification that incorporates the Ricci scalar $R$ and the trace of the energy-momentum tensor $T$. Motivated by…

General Relativity and Quantum Cosmology · Physics 2025-07-29 Parbati Sahoo

We construct phase-space structure of a typical higher-order theory of gravity, in the background of anisotropic Bianchi-1 mini-superspace, following `Modified Horowitz Formalism' as well as applying `Dirac Algorithm' (after taking care of…

General Relativity and Quantum Cosmology · Physics 2021-05-21 Subhra Debnath , Abhik Kumar Sanyal

A theory of exponential modified gravity which explains both early-time inflation and late-time acceleration, in a unified way, is proposed. The theory successfully passes the local tests and fulfills the cosmological bounds and,…

High Energy Physics - Theory · Physics 2011-04-22 E. Elizalde , S. Nojiri , S. D. Odintsov , L. Sebastiani , S. Zerbini

The present work is related to anisotropic cosmological evolution in metric $f(R)$ theory of gravity. The initial part of the paper develops the general cosmological dynamics of homogeneous anisotropic Bianchi-I spacetime in $f(R)$…

General Relativity and Quantum Cosmology · Physics 2019-01-23 Kaushik Bhattacharya , Saikat Chakraborty

Modified gravity theories are supposed to incorporate low-energy quantum-gravity effects and, at the same time, they could shed light into the dark matter and dark energy problems. Here we study a particular modification of general…

General Relativity and Quantum Cosmology · Physics 2017-08-28 Yuri Bonder , Gabriel Leon

We investigate the cosmological reconstruction in anisotropic universe for both homogeneous and inhomogeneous content of the universe. Special attention is attached to three interesting cases: Bianchi type-I, Bianchi type-III and…

General Relativity and Quantum Cosmology · Physics 2012-11-29 M. E. Rodrigues , M. J. S. Houndjo , D. Saez-Gomez , F. Rahaman

We study an inflationary scenario with a vector impurity. We show that the universe undergoes anisotropic inflationary expansion due to a preferred direction determined by the vector. Using the slow-roll approximation, we find a formula to…

High Energy Physics - Phenomenology · Physics 2008-11-26 Sugumi Kanno , Masashi Kimura , Jiro Soda , Shuichiro Yokoyama
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