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Related papers: G\"odel-type universes in f(T) gravity

200 papers

The Palatini $f(R,T)$ gravity theory is considered. The standard Einstein-Hilbert action is replaced by an arbitrary function of the Ricci scalar $R$ and of the trace $T$ of the energy-momentum tensor. In the Palatini approach, the Ricci…

General Relativity and Quantum Cosmology · Physics 2021-02-24 J. S. Gonçalves , A. F. Santos

We address the homogeneous in space and time (ST-homogeneous) G\"{o}del-type metrics within the cubic galileon theory, a particular class of generalized galileon theories. We check the consistency of such spacetimes for a physically…

General Relativity and Quantum Cosmology · Physics 2020-11-26 J. R. Nascimento , A. Yu. Petrov , P. Porfírio , A. F. Santos

In this paper, the G\"{o}del-type universes are examined within the framework of unimodular gravity. Since the existence of G\"{o}del solutions is intrinsically related to the presence of a cosmological constant in general relativity, one…

General Relativity and Quantum Cosmology · Physics 2025-06-16 R. Raimarda , A. F. Santos , R. Bufalo

Nonlocal gravity is a promising super-renormalizable or finite quantum gravity theory consistent with unitarity. In this paper, we focus on the classical equations of motion and explicitly show that a particular subclass of G\"{o}del-type…

General Relativity and Quantum Cosmology · Physics 2026-05-05 Zhe Zhao , Leonardo Modesto , Cosimo Bambi

In this paper, we investigate spherically symmetric perfect fluid gravitational collapse in metric $f(R)$ gravity. We take non-static spherically symmetric metric in the interior region and static spherically symmetric metric in the…

General Relativity and Quantum Cosmology · Physics 2011-01-17 M. Sharif , H. Rizwana Kausar

The stationary cosmological model without closed timelike curves of G\"odel type is obtained for the ideal dust matter source within the framework of the teleparallel gravity. For a specific choice of the teleparallel gravity parameters,…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Yu. N. Obukhov , T. Vargas

Causal anomalies in two Kaluza-Klein gravity theories are examined, particularly as to whether these theories permit solutions in which the causality principle is violated. It is found that similarly to general relativity the field…

General Relativity and Quantum Cosmology · Physics 2009-10-31 M. J. Reboucas , A. F. F. Teixeira

This manuscript aims to establish the gravitational junction conditions(JCs) for the $f(\mathcal{G},~T)$ gravity. In this gravitational theory, $f$ is an arbitrary function of Gauss-Bonnet invariant $\mathcal{G}$ and the trace of the…

General Relativity and Quantum Cosmology · Physics 2022-07-14 M. Z. Bhatti , Z. Yousaf , M. Yousaf

In this paper we study G\"{o}del universe in the framework of $f(R,T)$ modified theories of gravity, where $R$ is the curvature scalar and $T$ the trace of the energy momentum tensor. We demonstrate that G\"{o}del solution occurs in this…

General Relativity and Quantum Cosmology · Physics 2015-06-16 A. F. Santos

The Cauchy problem for metric-affine f(R)-gravity `a la Palatini and with torsion, in presence of perfect fluid matter acting as source, is discussed following the well-known Bruhat prescriptions for General Relativity. The problem results…

General Relativity and Quantum Cosmology · Physics 2009-08-24 S. Capozziello , S. Vignolo

We consider a string-inspired, gravitational theory of scalar and electromagnetic fields and we investigate the existence of axially-symmetric, G\"{o}del-type cosmological solutions. The neutral case is studied first and an "extreme"…

General Relativity and Quantum Cosmology · Physics 2016-08-25 P. Kanti , C. E. Vayonakis

We show that the G{\" o}del type Metrics in three dimensions with arbitrary two dimensional background space satisfy the Einstein-perfect fluid field equations. There exists only one first order partial differential equation satisfied by…

General Relativity and Quantum Cosmology · Physics 2015-05-13 Metin Gurses

The present work deals with cosmological solutions in $f(R,T)$ gravity theory for perfect fluid with constant equation of state ($\omega$). For a viable cosmological solution $\omega$ is restricted to $\omega<\dfrac{1}{3}$. Also depending…

General Relativity and Quantum Cosmology · Physics 2022-09-07 Akash Bose , Gopal Sardar , Subenoy Chakraborty

This paper is devoted to study the energy conditions in F(R,T) gravity for FRW universe with perfect fluid, where $R$ is the Ricci scalar and $T$ is the torsion scalar. We construct the general energy conditions in this theory and reduce…

General Relativity and Quantum Cosmology · Physics 2013-10-23 M. Sharif , S. Rani , R. Myrzakulov

In this paper, we investigate static spherically symmetric teleparallel F(T) gravity containing a perfect isotropic fluid. We first write the field equations and proceed to find new teleparallel F(T) solutions for perfect isotropic and…

General Relativity and Quantum Cosmology · Physics 2024-05-20 Alexandre Landry

Static spherically symmetric perfect fluid solutions are studied in metric $f(R)$ theories of gravity. We show that pressure and density do not uniquely determine $f(R)$ ie. given a matter distribution and an equation state, one cannot…

Astrophysics · Physics 2008-11-26 T. Multamaki , I. Vilja

Power-law solutions for $f(G)$ gravity coupled with perfect fluid have been studied for spatially flat universe. It is shown that despite the matter dominated and accelerating power-law solutions, the power-law solution exists for an…

General Relativity and Quantum Cosmology · Physics 2012-02-09 A. R. Rastkar , M. R. Setare , F. Darabi

We investigate models of future finite-time singularities in $f(T)$ theory, where $T$ is the torsion scalar. The algebraic function $f(T)$ is put as the teleparallel term $T$ plus an arbitrary function $g(T)$. A suitable expression of the…

General Relativity and Quantum Cosmology · Physics 2013-03-26 M. R. Setare , M. J. S. Houndjo

In an $n$-dimensional Friedmann-Robertson-Walker metric, it is rigorously shown that any analytical theory of gravity $f(R,{\cal G})$, where $R$ is the curvature scalar and $\cal G$ is the Gauss-Bonnet topological invariant, can be…

General Relativity and Quantum Cosmology · Physics 2019-10-02 Salvatore Capozziello , Carlo Alberto Mantica , Luca Guido Molinari

In this paper we assume that a perfect fluid is the source of the gravitational field while analyzing the solutions to the Einstein field equations.

General Relativity and Quantum Cosmology · Physics 2024-02-26 Krishnendu De , Uday Chand De , Ljubica Velimirovic