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Related papers: $f(\mathcal{G},\mathrm{\textit{T}})$ Gravity Bounc…

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In this paper, we consider a gravitational action containing a combination of the Ricci scalar, $R$, and the topological Gauss--Bonnet term, $G$. Specifically, we study the cosmological features of a particular class of modified gravity…

General Relativity and Quantum Cosmology · Physics 2023-03-15 Francesco Bajardi , Rocco D'Agostino

In this paper, in an extended theory of gravity, we have presented bouncing cosmological model at the backdrop of an isotropic, homogeneous space-time, in presence of general relativistic hydrodynamics (GRH). The scale factor has been…

General Relativity and Quantum Cosmology · Physics 2023-03-29 A. Y. Shaikh , Sankarsan Tarai , S. K. Tripathy , B. Mishra

Here we propose the extended modified gravity theory named as $f(R,G,\mathcal{T})$ gravity where $R$ is the Ricci scalar, $G$ is the Gauss-Bonnet invariant and $\mathcal{T}$ is the trace of the stress-energy tensor. We derive the…

General Relativity and Quantum Cosmology · Physics 2020-12-02 Ujjal Debnath

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

In this work by using a numerical analysis, we investigate in a quantitative way the late-time dynamics of scalar coupled $f(R,\mathcal{G})$ gravity. Particularly, we consider a Gauss-Bonnet term coupled to the scalar field coupling…

General Relativity and Quantum Cosmology · Physics 2022-07-27 S. D. Odintsov , V. K. Oikonomou , F. P. Fronimos

Einstein-Gauss-Bonnet (EGB) model is recently restudied in order to analyze new consequences in gravitation, modifying appropriately the Einstein-Hilbert action. The consequences in EGB cosmology are mainly geometric, with higher order…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-02 Miguel A. García-Aspeitia , A. Hernández-Almada

Theoretical arguments and cosmological observations suggest that Einstein's theory of general relativity needs to be modified at high energies. One of the best motivated higher-curvature extensions of general relativity is…

General Relativity and Quantum Cosmology · Physics 2017-08-04 Laura Sberna

A scalar-tensor theory of gravity is formulated in which $G$ and particle masses are allowed to vary. The theory yields a globally static cosmological model with no evolutionary timescales, no cosmological coincidences, and no flatness and…

General Physics · Physics 2015-10-01 Meir Shimon

This paper analyzes the possibility of bouncing and non-bouncing universes in the framework of four-dimensional Einstein-Gauss-Bonnet (4D-EGB) gravity, corresponding respectively to negative and positive coupling constants $\lambda$ of the…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-11 H. Khodabakhshi , M. Farhang , H. Lü

$f(P)$ gravity is a novel extension of ECG in which the Ricci scalar in the action is replaced by a function of the curvature invariant $P$ which represents the contractions of the Riemann tensor at the cubic order \cite{p}. The present…

General Relativity and Quantum Cosmology · Physics 2022-03-29 Snehasish Bhattacharjee

Some models within the framework of Gauss-Bonnet gravities are considered in the presence of a non-minimally coupled scalar field. By imposing a particular constraint on the scalar field coupling, an extension of the called…

General Relativity and Quantum Cosmology · Physics 2022-07-19 Sergei D. Odintsov , Diego Saez-Chillon Gomez , German S. Sharov

In this paper, the dynamical behavior of the accelerated expansion of the universe is studied within the framework of $f(T)$ gravity by considering a well-motivated functional form of $f(T)$. A specific form of the Hubble parameter is…

General Relativity and Quantum Cosmology · Physics 2026-03-20 Khomesh R. Patle , G. P. Singh

$f(T)$ cosmology has shown promise in explaining aspects of cosmic evolution. In this work, we analyze constraints on leading models of $f(T)$ gravity in the context of the recently released Pantheon+ data set, together with comparisons…

General Relativity and Quantum Cosmology · Physics 2023-05-22 Rebecca Briffa , Celia Escamilla-Rivera , Jackson Levi Said , Jurgen Mifsud

We investigate the validity of the generalized second law (GSL) of gravitational thermodynamics in the framework of f(T) modified teleparallel gravity. We consider a spatially flat FRW universe containing only the pressureless matter. The…

General Relativity and Quantum Cosmology · Physics 2012-04-12 K. Karami , A. Abdolmaleki

We investigate the cosmological evolution in a new modified teleparallel theory, called $f(T,B)$ gravity, which is formulated by connecting both $f(T)$ and $f(R)$ theories with a boundary term $B$. Here, $T$ is the torsion scalar in…

General Physics · Physics 2018-11-14 M. Zubair , Saira Waheed , M. Atif Fayyaz , Iftikhar Ahmad

We examine the cosmological dynamics of Einstein-Gauss-Bonnet gravity models in a four-dimensional spatially flat FLRW metric. These models are described by $f\left( R,\mathcal{G}\right) =f\left( R+\mu \mathcal{G}\right) $ theory of…

General Relativity and Quantum Cosmology · Physics 2025-12-10 Nikolaos Dimakis , Alex Giacomini , Genly Leon , Andronikos Paliathanasis , Ekaterina Pozdeeva , Sergey Vernov

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 derive conditions under which f(G) gravity models, whose Lagrangian densities f are written in terms of a Gauss-Bonnet term G, are cosmologically viable. The most crucial condition to be satisfied is that f_GG, the second derivative of f…

High Energy Physics - Theory · Physics 2009-04-18 Antonio De Felice , Shinji Tsujikawa

In the last dozen years a wide and variegated mass of observational data revealed that the universe is now expanding at an accelerated rate. In the absence of a well-based theory to interpret the observations, cosmography provides…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-30 Ester Piedipalumbo , Enrica Della Moglie , Roberto Cianci