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Related papers: Non-singular bouncing cosmology in $f(T, \mathcal{…

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We study a model for a non-singular cosmic bounce in N=1 supergravity, based on supergravity versions of the ghost condensate and cubic Galileon scalar field theories. The bounce is preceded by an ekpyrotic contracting phase which prevents…

High Energy Physics - Theory · Physics 2014-08-13 Michael Koehn , Jean-Luc Lehners , Burt A. Ovrut

In this work, we investigate the bouncing behavior of the universe within the framework of $f(R,L_m)$ gravity, using a simple form of $f(R,L_m)=\frac{R}{2}+L_m^\gamma$ (where $\gamma$ is a free model parameter) as previously studied. The…

General Relativity and Quantum Cosmology · Physics 2024-03-29 M. Koussour , N. Myrzakulov , Javlon Rayimbaev , Alnadhief H. A. Alfedeel , H. M. Elkhair

The basic aim of this manuscript is to investigate the cosmological solutions in the context of the modified $f(R, T)$ theory of gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor. For our current…

General Relativity and Quantum Cosmology · Physics 2024-03-26 Adnan Malik , Tayyaba Naz , Aimen Rauf , M. Farasat Shamir , Z. Yousaf

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 investigate bouncing scenario in the modified $f(T)$ gravity, $T$ being the torsion scalar. Attention is attached to the reconstruction of $f(T)$ able to describe type IV singular bouncing evolution, where we adopt as assumption that the…

General Relativity and Quantum Cosmology · Physics 2019-09-25 P. H. Logbo , M. J. S. Houndjo

We analyze the early-time isotropic cosmology in the so-called energy-momentum-squared gravity (EMSG). In this theory, a $T_{\mu\nu}T^{\mu\nu}$ term is added to the Einstein-Hilbert action, which has been shown to replace the initial…

General Relativity and Quantum Cosmology · Physics 2020-03-09 Ahmed H. Barbar , Adel M. Awad , Mohammad T. AlFiky

We apply the bottom-up reconstruction technique in the context of bouncing cosmology in F(R) gravity, where the starting point is a suitable ansatz of observable quantity (like spectral index or tensor to scalar ratio) rather than a priori…

General Relativity and Quantum Cosmology · Physics 2020-09-01 S. D. Odintsov , V. K. Oikonomou , Tanmoy Paul

We explore bounce scenarios in the framework of homogeneous and isotropic cosmological models with arbitrary spatial curvature in the theory of gravity with non-minimal derivative coupling. As expected, we find that there are no turning…

General Relativity and Quantum Cosmology · Physics 2025-02-11 S. V. Sushkov , R. G. Galeev

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

This study investigates the non-singular bounce within the framework of Myrzakulov-type $f(R,T) = R + \alpha T + \beta T^2$ gravity by adopting a Chaplygin gas equation of state. We employ two methodologies: a reconstruction scheme via a…

General Relativity and Quantum Cosmology · Physics 2026-04-24 Khandro K Chokyi , Abdel Nasser Tawfik , Surajit Chattopadhyay

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

We present a consistent effective theory that violates the null energy condition (NEC) without developing any instabilities or other pathological features. The model is the ghost condensate with the global shift symmetry softly broken by a…

High Energy Physics - Theory · Physics 2009-11-11 Paolo Creminelli , Markus A. Luty , Alberto Nicolis , Leonardo Senatore

We consider the possibility to produce a bouncing universe in the framework of scalar-tensor gravity models in which the scalar field potential may be negative, and even unbounded from below. We find a set of viable solutions with nonzero…

General Relativity and Quantum Cosmology · Physics 2015-07-15 B. Boisseau , H. Giacomini , D. Polarski , A. A. Starobinsky

We present a bounce universe in modified $f(Q,C)$ gravity considering linear as well as exponential form of gravity. Bounce cosmological models are introduced to remove the singularity problem of the early universe. A new quadratic boundary…

General Relativity and Quantum Cosmology · Physics 2025-08-07 Bhaswati Mandal , B. C. Paul

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 the context of Einstein gravity, if the null energy condition (NEC) is satisfied, the energy density in expanding space-times always decreases while in contracting space-times the energy density grows and the universe eventually…

General Relativity and Quantum Cosmology · Physics 2016-07-04 Anna Ijjas , Justin Ripley , Paul J. Steinhardt

In today's scenario, going beyond Einstein's theory of gravity leads us to some more complete and modified gravity theories. One of them is the $f(R,T)$ gravity in which $ R $ is the Ricci scalar, and $ T $ is the trace of the…

General Relativity and Quantum Cosmology · Physics 2022-01-04 P. K. Sahoo , Sanjay Mandal , Simran Arora

In this paper, we have shown the matter bounce scenario of the Universe in an extended symmetric teleparallel gravity, the f(Q) gravity. Motivated from the bouncing scenario and loop quantum cosmology (LQC), the form of the function $f(Q)$…

General Relativity and Quantum Cosmology · Physics 2023-02-06 A. S. Agrawal , B. Mishra , P. K. Agrawal

This article explores matter bounce non-singular cosmology in $f(R,L_m)$ gravity. We consider two non-linear $f(R,L_m)$ functional forms, specifically, $f(R,L_m) = \frac{R}{2} + \lambda R^2 + \alpha L_m$ and $f(R,L_m) = \frac{R}{2} + L_m…

General Relativity and Quantum Cosmology · Physics 2024-05-17 Lakhan V. Jaybhaye , Raja Solanki , P. K. Sahoo

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