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Related papers: Cosmic strings in $f\left(R,L_m\right)$ gravity

200 papers

As shown recently (arXiv:1903.08668), consistent thermodynamics of the Lorentzian Taub-NUT solutions with Misner strings present can be formulated provided a new pair of conjugate quantities (related to the NUT parameter) $\psi-N$ is…

High Energy Physics - Theory · Physics 2020-01-08 Alvaro Ballon Bordo , Finnian Gray , Robie A. Hennigar , David Kubiznak

We study massless cosmic strings which are one-dimensional objects moving with the speed of light. Perturbations of velocities of test bodies and anisotropy of cosmic microwave background generated by massless cosmic strings are analysed.…

General Relativity and Quantum Cosmology · Physics 2017-11-15 D. V. Fursaev

We obtain spacetimes generated by static and spinning magnetic string sources in Einstein Relativity with negative cosmological constant. Since the spacetime is asymptotically a cylindrical anti-de Sitter spacetime, we will be able to…

High Energy Physics - Theory · Physics 2009-11-07 Oscar J. C. Dias , Jose' P. S. Lemos

An introduction into the theory of locally anisotropic spaces (modelled as vector bundles provided with compatible nonlinear and distinguished linear connections and metric structures and containing as particular cases different types of…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Sergiu I. Vacaru

In this work, we linearize the field equations of $f(R)$ gravity using the Starobinsky model, $R+R^2/(6m^2)$, and examine the modifications to General Relativity. We derive an equation for the trace, $T$, of the energy-momentum tensor,…

General Relativity and Quantum Cosmology · Physics 2026-01-28 Roger Anderson Hurtado

This paper is devoted to investigate the recently proposed modified Gauss-Bonnet $f(\mathcal{G},T)$ gravity, with $\mathcal{G}$, the Gauss-Bonnet term, coupled with ${T}$, the trace of energy-momentum tensor. We have used the Noether…

General Relativity and Quantum Cosmology · Physics 2017-07-12 M. Farasat Shamir , Mushtaq Ahmad

A recent investigation shows that a local gauge string with a phenomenological energy momentum tensor, as prescribed by Vilenkin, is inconsistent in Brans-Dicke theory. In this work it has been shown that such a string is consistent in a…

General Relativity and Quantum Cosmology · Physics 2009-10-30 A. A. Sen , N. Banerjee

We study solutions for the Klein-Gordon equation with vector and scalar potentials of the Coulomb types under the influence of non-inertial effects in the space-time of topological defects. We also investigate a quantum particle described…

High Energy Physics - Theory · Physics 2018-02-14 L. C. N. Santos , C. C. Barros

We analyze the dynamics of scalar particles in gravity's rainbow considering the space-time of a cosmic string in this modified gravity. Thus, we solve the Klein-Gordon equation for two types of potential in which two possible rainbow…

General Relativity and Quantum Cosmology · Physics 2020-12-16 L. C. N. Santos , C. E. Mota , C. C. Barros , L. B. Castro , V. B. Bezerra

The four-dimensional superstring solutions define at low energy effective supergravity theories. A class of them extends successfully the validity of the standard model up to the string scale (${\cal O}(10^{17})~TeV$). We stress the…

High Energy Physics - Theory · Physics 2007-05-23 E. Kiritsis , C. Kounnas

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

We obtain a class of anisotropic spherically symmetric relativistic solutions of compact objects in hydrostatic equilibrium in the $f(R,T) =R+2\chi T$ modified gravity, where $R$ is the Ricci scalar, $T$ is the trace of the energy momentum…

General Physics · Physics 2020-09-18 S. Dey , A. Chanda , B. C. Paul

We study a cosmic string solution of an N=1-supersymmetric version of the Cremmer-Scherk-Kalb-Ramond (CSKR) Lagrangian coupled to a vector superfield by means of a topological mass term. The 2-form gauge potential is proposed to couple…

High Energy Physics - Theory · Physics 2009-11-07 C. N. Ferreira , M. B. D. S. M. Porto , J. A. Helayel-Neto

A solution of the vortex type is given in a six-dimensional $SU(2)\times U(1)$ pure gauge theory coupled to Einstein gravity in a compactified background geometry. We construct the solution of an effective abelian Higgs model in terms of…

High Energy Physics - Theory · Physics 2019-05-02 Atsushi Nakamula , Satoru Hirenzaki , Kiyoshi Shiraishi

We review various aspects of de Sitter spacetime in string theory: its status as an effective field theory spacetime solution, its relation to the vacuum energy problem in string theory, its (global) holographic definition in terms of two…

High Energy Physics - Theory · Physics 2023-08-30 Per Berglund , Tristan Hübsch , Djordje Minic

In this paper we derive some new invariant solutions of Einstein-Maxwell's field equations for string fluid as source of matter in cylindrically symmetric space-time with Variable Magnetic Permeability. We also discuss the physical and…

General Relativity and Quantum Cosmology · Physics 2015-01-09 Ahmad T. Ali , Anil Kumar Yadav , Farook Rahaman , Arkopriya Mallick

The relevant characteristic features, including energy per unit length and tension, of a cosmic string carrying massless fermionic currents in the framework of the Witten model in the neutral limit are derived through quantization of the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Christophe Ringeval

We recently developed a local description of the energy, momentum and angular momentum carried by the linearized gravitational field, wherein the gravitational energy-momentum tensor displays positive energy-density and causal energy-flux,…

General Relativity and Quantum Cosmology · Physics 2012-10-03 Luke M. Butcher , Michael Hobson , Anthony Lasenby

In this paper we obtain the space-time generated by a time-like current-carrying superconducting screwed cosmic string(TCSCS). This gravitational field is obtained in a modified scalar-tensor theory in the sense that torsion is taken into…

High Energy Physics - Theory · Physics 2011-07-19 V. B. Bezerra , C. N. Ferreira , J. B. Fonseca-Neto , A. A. R. Sobreira

In this paper we calculate the magnetic and electric self-forces, induced by the conical structure of a cosmic string space-time, on a long straight wire which presents either a constant current or a linear charge density. We also show how…

General Relativity and Quantum Cosmology · Physics 2016-08-31 E. R. Bezerra de Mello , V. B. Bezerra , C. Furtado , F. Moraes