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Related papers: Bounce cosmology in generalized modified gravities

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We study the geometric and physical foundations of Finsler gravity theories with metric compatible connections defined on tangent bundles, or (pseudo) Riemannian manifolds). There are analyzed alternatives to Einstein gravity (including…

Mathematical Physics · Physics 2013-03-15 Sergiu I. Vacaru

We explore the possibility of realizing a non-singular bounce in the early universe within the framework of modified gravity with spacetime torsion. In Einstein Cartan theory, torsion is embedded in the spacetime by adding an antisymmetric…

General Relativity and Quantum Cosmology · Physics 2026-01-21 Sonej Alam , Somasri Sen , Soumitra Sengupta

In this paper, we analyze the modified $f(\mathcal{R})$ gravity models in Friedmann--Lema\^{\i}tre--Robertson--Walker (FLRW) background. The actions of bouncing cosmology are studied under consideration of different viable models in…

General Relativity and Quantum Cosmology · Physics 2021-02-18 M. Ilyas , W. U. Rahman

We analyze the foundations of Finsler gravity theories with metric compatible connections constructed on nonholonomic tangent bundles, or (pseudo) Riemannian manifolds. There are considered "minimal" modifications of Einstein gravity…

General Physics · Physics 2013-03-18 Sergiu I. Vacaru

We present for the first time a Friedmann-like construction in the framework of an osculating Finsler-Randers-Sasaki geometry. In particular, we consider a vector field in the metric on a Lorentz tangent bundle, and thus the curvatures of…

General Relativity and Quantum Cosmology · Physics 2024-06-04 E. Kapsabelis , Emmanuel N. Saridakis , P. C. Stavrinos

We investigate the conditions for a bounce to occur in Friedmann-Robertson-Walker cosmologies for the class of fourth order gravity theories. The general bounce criterion is determined and constraints on the parameters of three specific…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Sante Carloni , Peter K. S. Dunsby , Deon Solomons

Finsler geometry is a natural and fundamental generalization of Riemann geometry. The Finsler structure depends on both coordinates and velocities. It is defined as a function on tangent bundle of a manifold. We use the Bianchi identities…

General Relativity and Quantum Cosmology · Physics 2007-11-14 Xin Li , Zhe Chang

In the framework of massive gravity with a de Sitter reference metric, we study homogeneous and isotropic solutions with positive spatial curvature. Remarkably, we find that bounces can occur when cosmological matter satisfies the strong…

High Energy Physics - Theory · Physics 2015-06-16 David Langlois , Atsushi Naruko

We reconstruct $F(R)$ gravity models with exponential and power-law forms of the scale factor in which bounce cosmology can be realized. We explore the stability of the reconstructed models with analyzing the perturbations from the…

High Energy Physics - Theory · Physics 2014-01-10 Kazuharu Bamba , Andrey N. Makarenko , Alexandr N. Myagky , Shin'ichi Nojiri , Sergei D. Odintsov

In this article, we review some aspects of gravitational field and cosmology based on Finsler and Finsler-like generalized metric structures. The geometrical framework of these spaces allows further investigation of locally-anisotropic…

General Relativity and Quantum Cosmology · Physics 2025-05-15 P. C. Stavrinos , A. Triantafyllopoulos

A bouncing scenario of a flat homogeneous and isotropic universe is explored by using the reconstruction technique for the power-law parametrization of the Hubble parameter in a modified gravity theory with higher-order curvature and trace…

General Relativity and Quantum Cosmology · Physics 2023-04-03 J. K. Singh , Harshna Balhara , Kazuharu Bamba , J. Jena

The present work analyzes the various conditions in which there can be a bouncing universe solution in f(R) gravity. In the article an interesting method, to analyze the bouncing FRW solutions in a spatially flat universe using f(R) gravity…

General Relativity and Quantum Cosmology · Physics 2014-12-09 Niladri Paul , Saikat Nil Chakrabarty , Kaushik Bhattacharya

We investigate bouncing solutions in the framework of the non-singular gravity model of Brandenberger, Mukhanov and Sornborger. We show that a spatially flat universe filled with ordinary matter undergoing a phase of contraction reaches a…

High Energy Physics - Theory · Physics 2010-04-06 L. Raul Abramo , Patrick Peter , Ivan Yasuda

A bouncing universe is a viable candidate to solve the initial singularity problem. Here we consider bouncing solutions in the context of $f(R,\mathcal{G})$ gravity by using an order reduction technique which allows one to find solutions…

General Relativity and Quantum Cosmology · Physics 2020-06-24 Bruno J. Barros , Elsa M. Teixeira , Daniele Vernieri

Over the last seventy years, many Finsler-type geometric and modified gravity theories have been elaborated. They have been formulated in terms of different classes of Finsler generating functions, metric and nonmetric structures, nonlinear…

Mathematical Physics · Physics 2026-03-19 Sergiu I. Vacaru

In the attempts to apply Finsler geometry to construct an extension of general relativity, the question about a suitable generalization of the Einstein equations is still under debate. Since Finsler geometry is based on a scalar function on…

General Relativity and Quantum Cosmology · Physics 2019-10-02 Manuel Hohmann , Christian Pfeifer , Nicoleta Voicu

We consider models of accelerating Universe elaborated for Finsler like gravity theories constructed on tangent bundles to Lorentz manifolds. In the osculating approximation, certain locally anisotropic configurations are similar to those…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-15 Panayiotis C. Stavrinos , Sergiu I. Vacaru

We study modifications of general relativity, GR, with nonlinear dispersion relations which can be geometrized on tangent Lorentz bundles. Such modified gravity theories, MGTs, can be modeled by gravitational Lagrange density functionals…

General Physics · Physics 2017-06-13 Panayiotis Stavrinos , Olivia Vacaru , Sergiu I. Vacaru

We explore bounce cosmology in $F(\mathcal{G})$ gravity with the Gauss-Bonnet invariant $\mathcal{G}$. We reconstruct $F(\mathcal{G})$ gravity theory to realize the bouncing behavior in the early universe and examine the stability…

High Energy Physics - Theory · Physics 2014-04-17 Kazuharu Bamba , Andrey N. Makarenko , Alexandr N. Myagky , Sergei D. Odintsov

We study a particular exact solution to the Born-Infeld determinantal gravity consisting of a cosmological model which undergoes a brusque bounce. The latter consists of an event characterized by a non-null (but finite) value of the squared…

General Relativity and Quantum Cosmology · Physics 2016-07-20 Franco Fiorini
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