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Within the framework of scalar-non-metricity gravity, we introduce a steep potential together with a power-law coupling function and investigate whether the acceleration phases of the universe can be consistently described by this model. In…

General Relativity and Quantum Cosmology · Physics 2025-10-06 Ghulam Murtaza , Avik De , Andronikos Paliathanasis

In this article, we focus on symmetric teleparallel gravity, a modification of General Relativity where gravity is described by the non-metricity of an affine connection, whose curvature and torsion vanish. In these theories, the…

General Relativity and Quantum Cosmology · Physics 2024-12-17 Manuel Hohmann , Vasiliki Karanasou

We consider static, spherically symmetric, electrically or/and magnetically charged configurations of a minimally coupled scalar field with an arbitrary potential $V(\phi)$ in general relativity. Using the inverse problem method, we obtain…

General Relativity and Quantum Cosmology · Physics 2008-11-26 K. A. Bronnikov , M. S. Chernakova

We generalise Einstein's formulation of the traceless Einstein equations to $f(R)$ gravity theories. In the case of the vacuum traceless Einstein equations, we show that a non-constant Weyl tensor leads via a conformal transformation to a…

General Relativity and Quantum Cosmology · Physics 2020-09-15 John D. Barrow , Spiros Cotsakis

A perfect fluid, spatially flat cosmology in a $f(T)$ model, derived from a recently proposed general Born-Infeld type theory of gravity is studied. Four dimensional cosmological solutions are obtained assuming the equation of state…

General Relativity and Quantum Cosmology · Physics 2014-12-04 Soumya Jana

We use the local value of the Hubble constant recently measured with 2.4% precision, as well as the latest compilation of cosmic chronometers data, together with standard probes such as Supernovae Type Ia and Baryon Acoustic Oscillation…

General Relativity and Quantum Cosmology · Physics 2016-08-10 Rafael C. Nunes , Supriya Pan , Emmanuel N. Saridakis

In this work, two originally separate adjustments for the Friedmann equations are concurrently considered. Firstly, the fractal structure of the black hole horizon region is imposed by the Barrow entropy. The second adjustment is the…

General Relativity and Quantum Cosmology · Physics 2024-06-13 Tuhina Ghorui , Prabir Rudra , Farook Rahaman

Teleparallel gravity is a modified theory of gravity for which the Ricci scalar $R$ of the underlying geometry in the action is replaced by an arbitrary functional form of torsion scalar $T$. In doing so, cosmology in $% f(T)$ gravity…

General Physics · Physics 2022-07-20 Sanjay Mandal , Snehasish Bhattacharjee , S. K. J. Pacif , P. K. Sahoo

We revisit models, within the Einstein-Cartan theory, where the cosmological constant $\Lambda$ is promoted to a variable, at the cost of allowing for torsion even in the absence of spinors. We remark that some standard notions about FRW…

General Relativity and Quantum Cosmology · Physics 2019-10-25 João Magueijo , Tom Złośnik

The article communicates gravitational baryogenesis in non-minimal $f(T)$ gravity and $f(T,B)$ teleparallel gravity where $T$ denote the torsion scalar and $B$ a boundary term. These extended teleparallel theories of gravity differ from the…

General Relativity and Quantum Cosmology · Physics 2020-06-08 Snehasish Bhattacharjee

We study the existence of hairy black holes in the generalized Einstein-Skyrme model. It is proven that in the BPS model limit there are no hairy black hole solutions, although the model admits gravitating (and flat space) solitons.…

High Energy Physics - Theory · Physics 2016-09-20 C. Adam , O. Kichakova , Ya. Shnir , A. Wereszczynski

The pursuit of understanding the mysteries surrounding dark energy has sparked significant interest within the field of cosmology. While conventional approaches, such as the cosmological constant, have been extensively explored, alternative…

General Relativity and Quantum Cosmology · Physics 2024-08-02 Oem Trivedi , Maxim Khlopov , Jackson Levi Said , Rafael C. Nunes

In the brane-world framework, we consider static, spherically symmetric configurations of a scalar field with the Lagrangian $(\d\phi)^2/2 - V(\phi)$, confined on the brane. We use the 4D Einstein equations on the brane obtained by…

General Relativity and Quantum Cosmology · Physics 2009-11-10 K. A. Bronnikov , S. B. Fadeev , A. V. Michtchenko

In the framework of spatially averaged inhomogeneous cosmologies in classical General Relativity, effective Einstein equations govern the regional and the global dynamics of averaged scalar variables of cosmological models. A particular…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Thomas Buchert

We consider tensor-vector theories with varying the space-time-matter coupling constant (varying Einstein velocity) in a spatially flat FRW universe. We examine the dynamics of this model by dynamical system method assuming a \Lambda CDM…

General Physics · Physics 2015-06-11 Azam Izadi , Ali Shojai , Mojtaba Nouradini

Over the past decades, the role of torsion in gravity has been extensively investigated along the main direction of bringing gravity closer to its gauge formulation and incorporating spin in a geometric description. Here we review various…

General Relativity and Quantum Cosmology · Physics 2016-09-09 Yi-Fu Cai , Salvatore Capozziello , Mariafelicia De Laurentis , Emmanuel N. Saridakis

In teleparallel gravity, we apply Lorenz type gauge fixing to cope with redundant degrees of freedom in the vierbein field. This condition is mainly to restore the Lorentz symmetry of the teleparallel torsion scalar. In cosmological…

General Relativity and Quantum Cosmology · Physics 2017-07-27 W. El Hanafy , G. G. L. Nashed

Transforming Penrose's intuitive picture of a strong cosmic censorship principle, that generically forbids the appearance of locally naked space-time singularities, into a formal mathematical proof, remains at present, one of the most…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Wenceslao Santiago-Germán

We consider three-dimensional gravity based on torsion. Specifically, we consider an extension of the so-called Teleparallel Equivalent of General Relativity in the presence of a scalar field with a self-interacting potential, where the…

General Relativity and Quantum Cosmology · Physics 2015-06-03 P. A. González , Joel Saavedra , Yerko Vásquez

We discuss a class of (local and non-local) theories of gravity that share same properties: i) they admit the Einstein spacetime with arbitrary cosmological constant as a solution; ii) the on-shell action of such a theory vanishes and iii)…

High Energy Physics - Theory · Physics 2015-06-04 Sergey N. Solodukhin
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