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Related papers: Bounce cosmology in generalized modified gravities

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In this paper, we have studied the bouncing behavior of the cosmological models formulated at the background of the Hubble function in the F(R, G) theory of gravity, where R and G denote the Ricci scalar and Gauss-Bonnet invariant. The…

General Relativity and Quantum Cosmology · Physics 2022-12-02 Santosh V Lohakare , Francisco Tello-Ortiz , S. K. Tripathy , B. Mishra

The main objective of this manuscript is to investigate the bouncing cosmology in the background of $f(\mathcal{Q})$ gravity, where $\mathcal{Q}$ defines the non-metricity. For this purpose, we use the reconstruction approach and consider a…

General Relativity and Quantum Cosmology · Physics 2024-04-02 M. Sharif , M. Zeeshan Gul , Nusrat Fatima

Several examples are known where quantum gravity effects resolve the classical big bang singularity by a bounce. The most detailed analysis has probably occurred for loop quantum cosmology of isotropic models sourced by a free, massless…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Martin Bojowald

We study the bounce and cyclicity realization in the framework of new gravitational scalar-tensor theories. In these theories the Lagrangian contains the Ricci scalar and its first and second derivatives, in a specific combination that…

General Relativity and Quantum Cosmology · Physics 2018-09-19 Emmanuel N. Saridakis , Shreya Banerjee , R. Myrzakulov

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

Scenario of a bouncing universe is one of the most active area of research to arrive at singularity free cosmological models. Different proposals have been suggested to avoid the so called 'big bang' singularity through the quantum aspect…

General Relativity and Quantum Cosmology · Physics 2022-10-26 Indrani Banerjee , Tanmoy Paul , Soumitra SenGupta

We consider the possibility to produce a bouncing universe in the framework of scalar-tensor gravity when the scalar field has a nonconformal coupling to the Ricci scalar. We prove that bouncing universes regular in the future with…

General Relativity and Quantum Cosmology · Physics 2016-06-01 B. Boisseau , H. Giacomini , D. Polarski

We study dynamics of induced gravity cosmological models with the sixth degree polynomial potentials, that have been constructed using the superpotential method. We find conditions on the potential under which exact bounce solutions exist…

General Relativity and Quantum Cosmology · Physics 2018-10-22 E. O. Pozdeeva , S. Yu. Vernov

In this article, we apply the Finsler spacetime to develop the Einstein field equations in the extension of modified geometry. Following Finsler geometry, which is focused on the tangent bundle with a scalar function, a scalar equation…

General Relativity and Quantum Cosmology · Physics 2025-02-11 Sourav Roy Chowdhury , Debabrata Deb , Farook Rahaman , Saibal Ray

The similarity between Finsler and Riemann geometry is an intriguing starting point to extend general relativity. The lack of quadratic restriction over the line element (color) naturally generalize the Riemannian case and breaks the local…

General Relativity and Quantum Cosmology · Physics 2015-06-11 A. P. Kouretsis , M. Stathakopoulos , P. C. Stavrinos

It is notoriously difficult to construct a stable non-singular bouncing cosmology that avoids all possible instabilities throughout the entire evolution of the universe. In this work, we explore whether a non-singular bounce driven by a…

General Relativity and Quantum Cosmology · Physics 2025-02-26 Lara Bohnenblust , Serena Giardino , Lavinia Heisenberg , Nadine Nussbaumer

We present a wide class of models which realise a bounce in a spatially flat Friedmann universe in standard General Relativity. The key ingredient of the theories we consider is a noncanonical, minimally coupled scalar field belonging to…

High Energy Physics - Theory · Physics 2011-11-14 Damien A. Easson , Ignacy Sawicki , Alexander Vikman

We investigate the cosmological applications of scalar-tensor theories that arise effectively from the Lorentz fiber bundle of a Finsler-like geometry. We first show that the involved nonlinear connection induces a new scalar degree of…

General Relativity and Quantum Cosmology · Physics 2019-12-20 Satoshi Ikeda , Emmanuel N. Saridakis , Panayiotis C. Stavrinos , Alkiviadis Triantafyllopoulos

Cuscuton Gravity is characterized as a scalar field that can be added to general relativity without introducing any new dynamical degrees of freedom on a cosmological background. Yet, it modifies gravity such that spacetime singularities…

High Energy Physics - Theory · Physics 2025-05-19 Amir Dehghani , Ghazal Geshnizjani , Jerome Quintin

Various types of Lagrange and Finsler geometries and the Einstein gravity theory, and modifications, can be modelled by nonholonomic distributions on tangent bundles/ manifolds when the fundamental geometric objects are adapted to nonlinear…

Mathematical Physics · Physics 2013-07-26 Sergiu I. Vacaru

Nonsingular cosmologies are investigated in the framework of f(R) gravity within the first order formalism. General conditions for bounces in isotropic and homogeneous cosmology are presented. It is shown that only a quadratic curvature…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Tomi S. Koivisto

For the anisotropic Universe filled with massless vector field in the General Relativity frame we obtain bouncing solution for one of scale factors. We obtain the Universe with finite maximal energy density, finite value of…

High Energy Physics - Theory · Physics 2015-05-30 Michal Artymowski , Zygmunt Lalak

We investigate the realization of a nonsingular bounce within the framework of Myrzakulov \( F(R,T) \) gravity. This modified gravitational theory uses a non-special connection that combines both curvature and torsion, giving rise to an…

General Relativity and Quantum Cosmology · Physics 2025-01-31 Andreas Lymperis , Gulgassyl Nugmanova , Almira Sergazina

We show how the large-scale cosmological dynamics can be obtained from the hydrodynamics of isotropic group field theory condensate states in the Gross-Pitaevskii approximation. The correct Friedmann equations are recovered in the…

General Relativity and Quantum Cosmology · Physics 2017-01-25 Daniele Oriti , Lorenzo Sindoni , Edward Wilson-Ewing

The occurrence of a bounce in FRW cosmology requires modifications of general relativity. An example of such a modification is the recently proposed Horava-Lifshitz theory of gravity, which includes a ``dark radiation'' term with a negative…

High Energy Physics - Theory · Physics 2011-03-31 Ewa Czuchry