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Related papers: Bounce cosmology in generalized modified gravities

200 papers

We study the dynamics of gauge-invariant scalar perturbations in cosmological scenarios with a modified Friedmann equation, such as quantum gravity bouncing cosmologies. We work within a separate universe approximation which captures…

General Relativity and Quantum Cosmology · Physics 2023-03-02 Steffen Gielen , Lisa Mickel

Finsler geometry is a natural generalization of pseudo-Riemannian geometry. It can be motivated e.g. by a modified version of the Ehlers-Pirani-Schild axiomatic approach to space-time theory. Also, some scenarios of quantum gravity suggest…

General Relativity and Quantum Cosmology · Physics 2015-06-23 Yakov Itin , Claus Lämmerzahl , Volker Perlick

We show that the f(T) gravitational paradigm, in which gravity is described by an arbitrary function of the torsion scalar, can provide a mechanism for realizing bouncing cosmologies, thereby avoiding the Big Bang singularity. After…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-07 Yi-Fu Cai , Shih-Hung Chen , James B. Dent , Sourish Dutta , Emmanuel N. Saridakis

We review the current status of Finsler-Lagrange geometry and generalizations. The goal is to aid non-experts on Finsler spaces, but physicists and geometers skilled in general relativity and particle theories, to understand the crucial…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sergiu I. Vacaru

If we imagine rewinding the universe to early times, the scale factor shrinks and the existence of a finite spatial volume may play a role in quantum tunnelling effects in a closed universe. It has recently been shown that such finite…

General Relativity and Quantum Cosmology · Physics 2023-11-15 Jean Alexandre , Katy Clough , Silvia Pla

We study an action integral for Finsler gravity obtained by pulling back an Einstein-Cartan-like Lagrangian from the tangent bundle to the base manifold. The vacuum equations are obtained imposing stationarity with respect to any section…

General Relativity and Quantum Cosmology · Physics 2022-11-29 A. Garcia-Parrado , E. Minguzzi

The resolution of the problem of cosmological singularity in the framework of gauge theories of gravitation is discussed. Generalized cosmological Friedmann equations for homogeneous isotropic models filled by interacting scalar fields and…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Albert V. Minkevich

In this article we present the cosmological equivalence between the relativistic Finsler-Randers cosmology, with dark energy and modified gravity constructions, at the background level. Starting from a small deviation from the quadraticity…

General Relativity and Quantum Cosmology · Physics 2013-12-17 Spyros Basilakos , Alexandros P. Kouretsis , Emmanuel N. Saridakis , Panayiotis Stavrinos

In this study, we explore the dynamics of the universe using a modified gravity model represented by $f(R, G, T)$, where $R$ is the Ricci scalar, $G$ is the Gauss-Bonnet invariant, and $T$ is the trace of the stress-energy tensor. The model…

General Relativity and Quantum Cosmology · Physics 2025-03-27 Farzad Milani

In this work we study non-singular{ bounce cosmology} in the context of the Lagrange multiplier generalized $F(R)$ gravity theory of gravity. We specify our study by using a specific variant form of the well known matter{ bounce cosmology},…

General Relativity and Quantum Cosmology · Physics 2020-01-08 Shin'ichi Nojiri , S. D. Odintsov , V. K. Oikonomou , Tanmoy Paul

An alternative to the Big Bang cosmologies is obtained by the Big Bounce cosmologies. In this paper, we study a bounce cosmology with a Type IV singularity occurring at the bouncing point, in the context of $F(R)$ modified gravity. We…

General Relativity and Quantum Cosmology · Physics 2017-01-17 S. D. Odintsov , V. K. Oikonomou

The theory of inflation is one of the fundamental and revolutionary developments of modern cosmology that became able to explain many issues of early universe in the context of the standard cosmological model (SCM). However, the initial…

General Relativity and Quantum Cosmology · Physics 2018-05-23 Jaume de Haro , Supriya Pan

We investigate non-singular bounce and cyclic cosmological evolutions in a universe governed by the extended nonlinear massive gravity, in which the graviton mass is promoted to a scalar-field potential. The extra freedom of the theory can…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-05 Yi-Fu Cai , Caixia Gao , Emmanuel N. Saridakis

A continuum mechanical theory with foundations in generalized Finsler geometry describes the complex anisotropic behavior of skin. A fiber bundle approach, encompassing total spaces with assigned linear and nonlinear connections,…

Soft Condensed Matter · Physics 2024-08-09 John D. Clayton

We locally classify all possible cosmological homogeneous and isotropic Landsberg-type Finsler structures, in 4-dimensions. Among them, we identify viable non-stationary Finsler spacetimes, i.e. those geometries leading to a physical causal…

We give an overview on the status and on the perspectives of Finsler gravity, beginning with a discussion of various motivations for considering a Finslerian modification of General Relativity. The subjects covered include Finslerian…

General Relativity and Quantum Cosmology · Physics 2018-12-05 Claus Lämmerzahl , Volker Perlick

We discuss the effects of a (possibly) negative $(1+z)^6$ type contribution to the Friedmann equation. No definite answer can be given as to the presence and magnitude of a particular mechanism, because any test using the general relation…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Tomasz Stachowiak , Marek Szydlowski

Applying the cosmological principle to Finsler spacetimes, we identify the Lie Algebra of symmetry generators of spatially homogeneous and isotropic Finsler geometries, thus generalising Friedmann-Lema\^{i}tre-Robertson-Walker geometry. In…

General Relativity and Quantum Cosmology · Physics 2020-05-06 Manuel Hohmann , Christian Pfeifer , Nicoleta Voicu

The implications of a deformed Heisenberg algebra on the Friedmann-Robertson-Walker cosmological models are investigated. We consider the Snyder non-commutative space in which the translation group is undeformed and the rotational…

General Relativity and Quantum Cosmology · Physics 2009-04-10 Marco Valerio Battisti

The generalized Finsler geometry, as well as Finsler geometry, is a generalization of Riemann geometry. The generalized Finsler geometry can be endowed with the Cartan connection. The generalized Finsler geometry and its Cartan connection…

General Physics · Physics 2007-05-23 Jian-Miin Liu