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Related papers: Bounce cosmology in $f(\mathcal{R})$ gravity

200 papers

We study how a cosmological bounce with a Type IV singularity at the bouncing point, can be generated by a classical vacuum $F(G)$ gravity. We focus our investigation on the behavior of the vacuum $F(G)$ theory near the Type IV singular…

General Relativity and Quantum Cosmology · Physics 2015-12-23 V. K. Oikonomou

We investigate which Jordan frame $F(R)$ gravity can describe a Type IV singular bouncing cosmological evolution, with special emphasis given near the point at which the Type IV singularity occurs. The cosmological bounce is chosen in such…

General Relativity and Quantum Cosmology · Physics 2015-08-06 S. D. Odintsov , V. K. Oikonomou

The usual Einstein's equations is modified as a one parameter family of equations in the framework of rainbow gravity. In this paper we derive the modified Friedmann-Robertson-Walker (FRW) equations when the cosmological evolution of…

General Relativity and Quantum Cosmology · Physics 2010-04-15 Yi Ling , Qingzhang Wu

The occurrence of a bounce in the 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…

High Energy Physics - Theory · Physics 2011-06-24 Ewa Czuchry

The main objective of this study is to investigate the phenomenon of the bouncing scenario of the universe. The most widely recognized cosmological framework is the standard cosmological model, sometimes referred to as the Big Bang model.…

General Relativity and Quantum Cosmology · Physics 2024-02-13 A. S. Agrawal

We study the bounce cosmology to construct a singularity-free $f(\mathcal{R})$ model using the reconstruction technique. The formulation of the $f(\mathcal{R})$ model is based on the Raychaudhari equation, a key element employed in…

General Relativity and Quantum Cosmology · Physics 2024-07-30 Gaurav N. Gadbail , Simran Arora , P. K. Sahoo , Kazuharu Bamba

We consider certain aspects of cosmological dynamics of a spatially curved Universe in $f(T)$ gravity. Local analysis allows us to find conditions for bounces and for static solutions; these conditions appear to be in general less…

General Relativity and Quantum Cosmology · Physics 2021-06-10 Maria A. Skugoreva , Alexey V. Toporensky

In $f(T)$ gravity, the theory modifies the gravitational action by introducing a function of the torsion scalar $T$. This approach allows for a different treatment of gravity than general relativity, particularly in cosmological contexts.…

General Relativity and Quantum Cosmology · Physics 2024-10-08 S. Davood Sadatian , S. Mohamad Reza Hosseini

We investigate the bounce cosmology induced by inhomogeneous viscous fluids in FRW space-time (non necessarly flat), taking into account the early-time acceleration after the bounce. Different forms for the scale factor and several examples…

General Relativity and Quantum Cosmology · Physics 2015-09-21 Ratbay Myrzakulov , Lorenzo Sebastiani

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

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

In this paper, working in a Friedman-Lemaitre-Robertson-Walker (FLRW), first, in the flat case, we recover the generalized Friedman equation of Quantum Loop cosmology, and therefore the cosmological bounce, in the framework of modified…

General Relativity and Quantum Cosmology · Physics 2021-01-20 Alessandro Casalino , Bruno Sanna , Lorenzo Sebastiani , Sergio Zerbini

We develop a Gauss-Bonnet extension of Loop Quantum Cosmology, by introducing holonomy corrections in modified $F(\mathcal{G})$ theories of gravity. Within the context of our formalism, we provide a perturbative expansion in the critical…

General Relativity and Quantum Cosmology · Physics 2015-12-16 J. Haro , A. N. Makarenko , A. N. Myagky , S. D. Odintsov , V. K. Oikonomou

In this paper, we have presented a bouncing cosmological model of the Universe in an extended theory of gravity. The dynamical behaviour of the model obtained from the flat FLRW space-time along with the violation of null energy condition…

General Relativity and Quantum Cosmology · Physics 2022-04-22 A. S. Agrawal , Francisco Tello-Ortiz , B. Mishra , S. K. Tripathy

We have investigated some bouncing models in the framework of an extended gravity theory where the usual Ricci scalar in the gravitational action is replaced by a sum of the Ricci scalar and a term proportional to the trace of the energy…

General Relativity and Quantum Cosmology · Physics 2019-05-24 Sunil Kumar Tripathy , Rakesh Kumar Khuntia , Priyabrata Parida

As is known, in modified cosmological theories of gravity many of the cosmologies which could not be generated by standard Einstein gravity, can be consistently described by $F(R)$ theories. Using known reconstruction techniques, we…

General Relativity and Quantum Cosmology · Physics 2015-09-16 V. K. Oikonomou

We provide a detailed analysis of Friedmann-Robertson-Walker universes in a wide range of scalar-tensor theories of gravity. We apply solution-generating methods to three parametrised classes of scalar-tensor theory which lead naturally to…

General Relativity and Quantum Cosmology · Physics 2009-10-28 John D. Barrow , Paul Parsons

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

A bouncing Universe avoids the big-bang singularity. Using the time-like and null Raychaudhhuri equations, we explore whether the bounce near the big-bang, within a broad spectrum of modified theories of gravity, allows for cosmologically…

General Relativity and Quantum Cosmology · Physics 2025-11-12 Saurya Das , S. Shajidul Haque , Seturumane Tema

We provide an $F(R)$ gravity description of a $\Lambda$CDM bouncing model, without the need for matter fluids or for cosmological constant. As we explicitly demonstrate, the two cosmological eras that constitute the $\Lambda$CDM bouncing…

General Relativity and Quantum Cosmology · Physics 2015-06-23 S. D. Odintsov , V. K. Oikonomou