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We investigate the bounce and cyclicity realization in the framework of weakly broken galileon theories. We study bouncing and cyclic solutions at the background level, reconstructing the potential and the galileon functions that can give…

General Relativity and Quantum Cosmology · Physics 2017-04-07 Shreya Banerjee , Emmanuel N. Saridakis

We examine non-singular bounce cosmology within the framework of a phantom scalar field coupled to the Gauss-Bonnet term in both non-viscous and bulk-viscous cases. Using the scale factor ansatz…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-07 Khandro K. Chokyi , Surajit Chattopadhyay

Two parameters scale factor leading to bouncing cosmology is considered. We show that at some model parameters we obtain the deceleration parameter $q_0\approx -0.535$ at the current epoch which is in agreement with the Planck data. The…

General Physics · Physics 2026-05-18 S. I. Kruglov

We investigate evolutional paths of an extended quintessence with a non-minimally coupled phantom scalar field $\psi$ to the Ricci curvature. The dynamical system methods are used to investigate typical regimes of dynamics at the late time.…

High Energy Physics - Theory · Physics 2008-11-26 Orest Hrycyna , Marek Szydlowski

Some dynamical properties of a bouncing ball model under the presence of an external force modeled by two nonlinear terms are studied. The description of the model is made by use of a two dimensional nonlinear measure preserving map on the…

Chaotic Dynamics · Physics 2009-03-11 Edson D. Leonel , Mario Roberto Silva

We investigate the post-bounce background dynamics in a certain class of single bounce scenarios studied in the literature, in which the cosmic bounce is driven by a scalar field with negative exponential potential such as the ekpyrotic…

General Relativity and Quantum Cosmology · Physics 2021-10-27 Ok Song An , Jin U Kang , Thae Hyok Kim , Ui Ri Mun

We explore the dynamics of FLRW cosmologies which consist of dark matter, radiation and dark energy with a quadratic equation of state. Standard cosmological singularities arise due to energy conditions which are violated by dark energy,…

General Relativity and Quantum Cosmology · Physics 2023-05-19 Molly Burkmar , Marco Bruni

We consider modified theories of gravity with a direct coupling between matter and geometry, denoted by an arbitrary function in terms of the Ricci scalar. Due to such a coupling, the matter stress tensor is no longer conserved and there is…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Yousef Bisabr

In this paper we discuss models satisfying the limiting curvature condition. For this purpose we modify the Einstein-Hilbert action by adding a term which restricts the growth of curvature. We analyze cosmological solutions in such models.…

High Energy Physics - Theory · Physics 2021-11-30 Valeri P. Frolov , Andrei Zelnikov

We study the emergence of cosmic hysteresis in cyclic bouncing universes within the framework of analytically reconstructed $f(R)$ gravity. Using exact bouncing scale factor solutions of exponential and power-law forms, we reconstruct the…

General Relativity and Quantum Cosmology · Physics 2025-08-15 Aritra Sanyal , Praveen Kumar Dhankar , Albert Munyeshyaka , Safiqul Islam , Farook Rahaman

In this paper, we have studied the dynamical aspects of some cosmological models in an isotropic space-time within the framework of an extended gravity theory. Two accelerating cosmological models are presented with quasi-de Sitter (QDS)…

General Relativity and Quantum Cosmology · Physics 2021-12-24 B. Mishra , Eesha Gadia , S. K. Tripathy

In this investigation, we perform an observational statistical analysis in the theory of $ f(R, L_m) $ gravity. The proposed theoretical model is based on the Ricci scalar's non-linear contribution. We use a distinct parameterization for…

General Relativity and Quantum Cosmology · Physics 2024-08-30 J. K. Singh , Shaily , Akanksha Singh , Harshna Balhara , Joao R. L. Santos

A scalar-tensor theory of gravity is considered wherein the gravitational coupling $G$ and the speed of light $c$ are admitted as space-time functions and combine to form the definition of the scalar field $\phi$. The varying $c$…

General Relativity and Quantum Cosmology · Physics 2023-04-05 Rodrigo R. Cuzinatto , Rajendra P. Gupta , Pedro J. Pompeia

We investigate cosmological models with a linear inhomogeneous time-dependent equation of state for the dark energy, coupled with dark matter, leading to a bounce cosmology. Equivalent descriptions in terms of the equation-of-state…

General Relativity and Quantum Cosmology · Physics 2014-05-07 I. Brevik , V. V. Obukhov , A. V. Timoshkin

We consider f(R,T) modified theory of gravity in which, in general, the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar and the trace of the energy-momentum tensor. We indicate that in this type of the theory,…

General Relativity and Quantum Cosmology · Physics 2016-10-05 Raziyeh Zaregonbadi , Mehrdad Farhoudi

We investigate the emergence of cosmic hysteresis in cyclic bouncing cosmologies within the framework of $f(R)$ modified gravity theories. Building upon previous studies that explored hysteresis phenomena in braneworld and…

General Relativity and Quantum Cosmology · Physics 2025-06-12 Aritra Sanyal

Accelerating cosmological models are constructed in a modified gravity theory dubbed as $f(R,T)$ gravity at the backdrop of an anisotropic Bianchi type-III universe. $f(R,T)$ is a function of the Ricci scalar $R$ and the trace $T$ of the…

General Relativity and Quantum Cosmology · Physics 2017-06-21 S K Sahu , S K Tripathy , P K Sahoo , A Nath

We study the cosmological dynamics of non-minimally coupled matter models using the Brown's variational approach to relativistic fluids in General Relativity. After decomposing the Ricci scalar into a bulk and a boundary term, we construct…

General Relativity and Quantum Cosmology · Physics 2025-12-22 Hala A. Ashi , Christian G. Boehmer , Antonio d'Alfonso del Sordo , Erik Jensko

This work deals with thick braneworld models, in an environment where the Ricci scalar is changed to accommodate the addition of two extra terms, one depending on the Ricci scalar itself, and the other, which takes into account the trace of…

High Energy Physics - Theory · Physics 2015-03-02 D. Bazeia , A. S. Lobao , R. Menezes

We study Proca theory with non-minimal coupling to gravity through the Ricci tensor and Ricci scalar interactions. We show that in the homogeneous and isotropic Universe together with cosmological constant, the temporal component of the…

General Relativity and Quantum Cosmology · Physics 2025-05-27 Antonio De Felice , Anamaria Hell
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