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Related papers: Bouncing cosmological models in $f(R,L_m)$ gravity

200 papers

Using the reconstruction method, we investigate which $F(R)$ theories, with or without the presence of matter fluids, can produce the matter bounce scenario of holonomy corrected Loop Quantum Cosmology. We focus our study in two limits of…

General Relativity and Quantum Cosmology · Physics 2015-01-07 S. D. Odintsov , V. K. Oikonomou

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

This paper studies a generic fourth-order theory of gravity with Lagrangian density $f(R,R_c^2,R_m^2, \mathscr{L}_m)$. By considering explicit $R^2$ dependence and imposing the "coherence condition" $f_{R^2}\!=\!f_{R_m^2}\!=\!…

General Relativity and Quantum Cosmology · Physics 2015-07-14 David Wenjie Tian , Ivan Booth

We confront various nonsingular bouncing cosmologies with the recently released BICEP2 data and investigate the observational constraints on their parameter space. In particular, within the context of the effective field approach, we…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-19 Yi-Fu Cai , Jerome Quintin , Emmanuel N. Saridakis , Edward Wilson-Ewing

Some bouncing models are investigated in the framework of an extended theory of gravity. The extended gravity model is a simple extension of the General Relativity where an additional matter geometry coupling is introduced to account for…

General Relativity and Quantum Cosmology · Physics 2021-06-10 S K Tripathy , B Mishra , Saibal Ray , Rikpratik Sengupta

To find more deliberate f(R,T) cosmological solutions, we proceed our previous paper further by studying some new aspects of the considered models via investigation of some new cosmological parameters/quantities to attain the most…

General Relativity and Quantum Cosmology · Physics 2017-05-23 Hamid Shabani , Mehrdad Farhoudi

In this work, we analyzed the improved Deser-Woodard non-local gravity over the background of five different bouncing cosmologies, whose premise is avoid the initial singular state of the universe. We developed the numerical solution for…

General Relativity and Quantum Cosmology · Physics 2022-06-01 D. Jackson , R. Bufalo

We examine the full nonlinear dynamics of closed FRW universes in the framework of D-branes formalism. Friedmann equations contain additional terms arising from the bulk-brane interaction that provide a concrete model for nonsingular…

General Relativity and Quantum Cosmology · Physics 2013-01-23 Rodrigo Maier , Ivano Damião Soares , Eduardo Valentino Tonini

A non-singular bouncing cosmology is generically obtained in loop quantum cosmology due to non-perturbative quantum gravity effects. A similar picture can be achieved in standard general relativity in the presence of a scalar field with a…

General Relativity and Quantum Cosmology · Physics 2014-03-17 Yi-Fu Cai , Edward Wilson-Ewing

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 study, the Universe's rip cosmology theories have been provided for the $f(Q,C)$ gravity theory, where $Q$ and $C$ stand for the non-metricity scalar and boundary term. We assumed $f(Q,C)=\alpha Q^{n}+\beta C$ and analyzed the…

General Relativity and Quantum Cosmology · Physics 2024-04-30 Amit Samaddar , S. Surendra Singh , Shah Muhammad , Euaggelos E. Zotos

In order to constrain $f(R,L_{m})$ gravity from theoretical aspects, its energy conditions are derived in this paper. These energy conditions given by us are quite general and can be degenerated to the well-known energy conditions in…

General Physics · Physics 2015-06-12 Jun Wang , Kai Liao

We present a model of non-relativistic gravitational theory which is power-counting renormalizable in 3+1 dimensional spacetime. When applied to cosmology, the relativity-violation terms lead to a dark radiation component, which can give…

High Energy Physics - Theory · Physics 2009-11-13 Yi-Fu Cai , Emmanuel N. Saridakis

In this paper, we have explored the field equations of f(T, B) gravity as an extension of teleparallel gravity in an isotropic and homogeneous space time. In the basic formalism developed, the dynamical parameters are derived by…

General Relativity and Quantum Cosmology · Physics 2024-09-27 S. A. Kadam , Jackson Levi Said , B. Mishra

In this paper, we explore modified gravity in the framework of $f(R, \mathcal{L}_m)$ theories by reconstructing the function $f(\mathcal{L}_m)$, where $\mathcal{L}_m = \rho$ is the matter Lagrangian, under the assumption of a pressureless,…

General Relativity and Quantum Cosmology · Physics 2025-06-12 Y. Kalpana Devi , S. A. Narawade , B. Mishra

The article investigates cosmological applications of $f(Q)$ theories in a non-coincident formalism. We explore a new $f(Q)$ theory dynamics utilizing a non-vanishing affine connection involving a non-constant function…

General Relativity and Quantum Cosmology · Physics 2024-10-03 Sneha Pradhan , Raja Solanki , P. K. Sahoo

We illustrate a general reconstruction procedure for mimetic gravity. Focusing on a bouncing cosmological background, we derive general properties that must be satisfied by the function $f(\Box\phi)$ implementing the limiting curvature…

General Relativity and Quantum Cosmology · Physics 2019-05-10 Marco de Cesare

We have investigated the cosmological consequences of the model in the recently developed gravity theory [Haghani and Harko, \textit{Eur. Phys. J. C} \textbf{81} (2021) 615.] using a non-linear form of the $f(R,T,L_{m})$ function and the…

General Relativity and Quantum Cosmology · Physics 2025-09-15 Dinesh Chandra Maurya , Rashid Zia

Bounce cosmological models containing a dark viscous fluid in a spatially flat Friedmann-Robertson-Walker (FRW) universe are considered. The universe evolution is described in terms of generalized equation of state (EoS) parameters, in…

General Relativity and Quantum Cosmology · Physics 2024-11-19 E. Elizalde , A. V. Yurov , A. V. Timoshkin

We develop a non-singular bouncing cosmology using a non-trivial coupling of general relativity to fermionic fields. The usual Big Bang singularity is avoided thanks to a negative energy density contribution from the fermions. Our theory is…

General Relativity and Quantum Cosmology · Physics 2014-12-10 Stephon Alexander , Cosimo Bambi , Antonino Marciano , Leonardo Modesto