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Related papers: Non-local gravity in bouncing cosmology scenarios

200 papers

We investigate a particular type of classical nonsingular bouncing cosmology, which results from general relativity if we allow for degenerate metrics. The simplest model has a matter content with a constant equation-of-state parameter and…

General Relativity and Quantum Cosmology · Physics 2019-10-23 F. R. Klinkhamer , Z. L. Wang

We consider nonlocal modification of the Einstein theory of gravity in framework of the pseudo-Riemannian geometry. The nonlocal term has the form $\mathcal{H}(R) \mathcal{F}(\Box)\mathcal {G}(R)$, where $\mathcal{H}$ and $\mathcal{G}$ are…

High Energy Physics - Theory · Physics 2015-08-25 Ivan Dimitrijevic , Branko Dragovich , Jelena Grujic , Zoran Rakic

We investigate the cosmological dynamics of nonlocally corrected gravity involving a function of the inverse d'Alembertian acting on the Gauss-Bonnet term. Casting the dynamical equations in local form, we derive the reconstruction…

General Relativity and Quantum Cosmology · Physics 2020-03-12 Emilio Elizalde , Ekaterina O. Pozdeeva , Sergey Yu. Vernov

The cosmological dynamics of a non-locally corrected gravity theory, involving a power of the inverse d'Alembertian, is investigated. Casting the dynamical equations into local form, the fixed points of the models are derived, as well as…

General Relativity and Quantum Cosmology · Physics 2018-11-06 E. Elizalde , S. D. Odintsov , E. O. Pozdeeva , S. Yu. Vernov

We consider the cosmology of modified gravity models in which Newton's constant is distorted by a function of the inverse d'Alembertian acting on the Ricci scalar. We derive a technique for choosing the distortion function so as to fit an…

General Relativity and Quantum Cosmology · Physics 2009-08-24 C. Deffayet , R. P. Woodard

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

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

We discuss how the modifications of the standard Einstein's equations needed to support the cosmological bounce can at the same time lead to vanishing of the well known cosmological constant problem, while also studying the effects of…

General Relativity and Quantum Cosmology · Physics 2025-01-24 Petar Pavlović , Marko Sossich

We consider general curvature-invariant modifications of the Einstein-Hilbert action that become important only in regions of extremely low space-time curvature. We investigate the far future evolution of the universe in such models,…

In this paper, we briefly review highlights of nonlocal de Sitter gravity based on the nonlocal term $ \sqrt{R - 2\Lambda}\ \mathcal{F}(\Box)\ \sqrt{R - 2\Lambda }$ in the Einstein-Hilbert action without matter sector. This nonlocal de…

General Relativity and Quantum Cosmology · Physics 2023-12-29 Ivan Dimitrijevic , Branko Dragovich , Zoran Rakic , Jelena Stankovic

We consider non-local Integral Kernel Theories of Gravity in a homogeneous and isotropic universe background as a possible scenario to drive the cosmic history. In particular, we investigate the cosmological properties of a gravitational…

General Relativity and Quantum Cosmology · Physics 2024-09-02 Salvatore Capozziello , Rocco D'Agostino , Orlando Luongo

This paper is devoted to a simple nonlocal de Sitter gravity model and its exact vacuum cosmological solutions. In the Einstein-Hilbert action with $\Lambda$ term, we introduce nonlocality by the following way: $R - 2 \Lambda =…

General Relativity and Quantum Cosmology · Physics 2022-12-28 Ivan Dimitrijevic , Branko Dragovich , Zoran Rakic , Jelena Stankovic

We investigate a bounce realization in the framework of higher order curvature in $ f(R,T) $ modified theory of gravity. We perform a detailed analysis of the cosmological parameters to explain the contraction phase, the bounce phase, and…

General Relativity and Quantum Cosmology · Physics 2023-07-19 J. K. Singh , Shaily , Akanksha Singh , Aroonkumar Beesham , Hamid Shabani

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

We study accelerating cosmological solutions of a general class of non-linear gravities which depend on Gauss-Bonnet and other higher derivative invariants. To achieve this goal a local formulation with auxiliary scalars for arbitrary…

High Energy Physics - Theory · Physics 2009-01-16 Salvatore Capozziello , Emilio Elizalde , Shin'ichi Nojiri , Sergei D. Odintsov

We present exact non-singular bounce solutions of general relativity in the presence of a positive cosmological constant and an electromagnetic field, without any exotic matter. The solutions are distinguished by being spatially…

High Energy Physics - Theory · Physics 2019-10-02 Andres Anabalon , Sebastian F. Bramberger , Jean-Luc Lehners

We present a new bouncing cosmological solution of the non-local theory known as infinite derivative gravity, which goes beyond the recursive ansatz, ${\Box R = r_1 R +r_2}$. The non-local field equations are evaluated using the spectral…

General Relativity and Quantum Cosmology · Physics 2022-02-24 Ivan Kolář , Francisco José Maldonado Torralba , Anupam Mazumdar

Non-local gravity cosmologies are considered under the standard of Noether Symmetry Approach. In particular, we focus on non-local theories whose gravitational actions depend on curvature and Gauss-Bonnet scalar invariants. Specific…

General Relativity and Quantum Cosmology · Physics 2020-12-03 Francesco Bajardi , Salvatore Capozziello , Daniele Vernieri

In this paper, we study non-local $F(R)$-mimetic gravity. We implement mimetic gravity in the framework of non-local $F(R)$-theories of gravity. Given some specific class of models and using a potential on the mimetic field, we investigate…

General Relativity and Quantum Cosmology · Physics 2016-06-01 Ratbay Myrzakulov , Lorenzo Sebastiani

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