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In the present work, we study the dynamical evolution of an homogeneous and anisotropic KS cosmological model, considering general relativity as the gravitational theory, such that there are three different perfect fluids in the matter…

General Relativity and Quantum Cosmology · Physics 2022-06-15 G. Oliveira-Neto , D. L. Canedo , G. A. Monerat

We consider the brane Kantowski-Sachs universe when bulk space is five dimensional anti-de Sitter obeying a linear equation of state of the form $p=(\gamma -1)\rho +p_{0}$, where $ \gamma,\:p_{0}$ are a parameters. In this framework we…

General Relativity and Quantum Cosmology · Physics 2015-12-02 G. S. Khadekar

In the present work, we analyzed the Kantowski-Sachs cosmological model along with teleparallel gravity, where a bulk viscous fluid containing one-dimensional cosmic strings serves as the source for the energy$-$momentum tensor. To obtain…

General Relativity and Quantum Cosmology · Physics 2024-11-11 S. R. Bhoyar , Yash B. Ingole

The $f(T)$ theory is recently proposed to explain the present cosmic accelerating expansion of the universe. $f(T)$ theory is an extension of Teleparallel theory of gravity, where $T$ is the torsion scalar. This paper contains the…

General Relativity and Quantum Cosmology · Physics 2015-02-04 M. Jamil Amir , M. Yussouf

In this paper we investigate, from the dynamical systems perspective, the evolution of a Kantowski-Sachs metric in a generic class of $f(R)$ models. We present conditions (i. e., differentiability conditions, existence of minima, monotony…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-27 Genly Leon , Armando A. Roque

A consisten quantization with a clear notion of time and evolution is given for the anisotropic Kantowski-SDachs cosmological model. It is shown that a suitable coordinate choice allows to obtain a solution of the Wheeler-DeWitt equation in…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Claudio Simeone

Although it is not a fundamental question, to determine exact and general solutions for a given theory has advantages over a numerical integration in many specific cases. Of course, respecting the peculiarities of the problem. Revisiting…

General Relativity and Quantum Cosmology · Physics 2019-11-12 B. Terezon , M. Campos

In this paper we study the quantum cosmological Kantowski-Sachs model and solve the Wheeler-DeWitt equation in minisuperspace to obtain the wave function of the corresponding universe. The perfect fluid is described by the Schutz's…

General Relativity and Quantum Cosmology · Physics 2016-11-11 F. G. Alvarenga , R. Fracalossi , R. C. Freitas , S. V. B. Gonçalves

The Kantowski-Sachs cosmological model sourced by a Skyrme field and a cosmological constant is considered in the framework of General Relativity. Assuming a constant radial profile function for the hedgehog ansatz, the Skyrme contribution…

General Relativity and Quantum Cosmology · Physics 2015-04-06 Luca Parisi , Ninfa Radicella , Gaetano Vilasi

We consider brane Kantowski-Sachs Universe when bulk space is five-dimensional Anti-deSitter space. The corresponding cosmological equations with perfect fluid are written. For several specific choices of relation between energy and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. N. Makarenko , V. V. Obukhov , K. E. Osetrin

In the context of the modified teleparallel $f(T, B)$-theory of gravity, we consider a homogeneous and anisotropic background geometry described by the Kantowski-Sachs line element. We derive the field equations and investigate the…

General Relativity and Quantum Cosmology · Physics 2022-07-19 Genly Leon , Andronikos Paliathanasis

We construct general anisotropic cosmological scenarios governed by an $f(R)$ gravitational sector. Focusing then on Kantowski-Sachs geometries in the case of $R^n$-gravity, and modelling the matter content as a perfect fluid, we perform a…

General Relativity and Quantum Cosmology · Physics 2011-08-19 Genly Leon , Emmanuel N. Saridakis

Quantum cosmology is studied within the framework of the minimal quantum gravity theory proposed by Ho\v{r}ava. For this purpose we choose the Kantowski-Sachs (KS) model and construct the corresponding Wheeler-DeWitt equation. We study the…

General Relativity and Quantum Cosmology · Physics 2013-05-31 O. Obregón , J. A. Preciado

Stability analysis of the Kantowski-Sachs type universe in pure higher derivative gravity theory is studied in details. The non-redundant generalized Friedmann equation of the system is derived by introducing a reduced one dimensional…

High Energy Physics - Theory · Physics 2009-11-11 W. F. Kao

In this paper, we have studied Brans-Dicke Cosmology in anisotropic Kantowski-Sachs space-time model; considering variation of the velocity of light. We have addressed the flatness problem considering both the cases namely, (i) when the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Subenoy Chakraborty , N. C. Chakraborty , Ujjal Debnath

Following recent considerations of a non-zero value for the vacuum energy density and the realization that a simple Kantowski-Sachs model might fit the classical tests of cosmology, we study the qualitative behavior of three anisotropic and…

Astrophysics · Physics 2011-04-15 Paulo Aguiar , Paulo Crawford

Using s-wave and large N approximation the one-loop effective action for 2d dilaton coupled scalars and spinors which are obtained by spherical reduction of 4d minimal matter is found. Quantum effective equations for reduced Einstein…

High Energy Physics - Theory · Physics 2009-09-17 S. Nojiri , O. Obregon , S. D. Odintsov , K. E. Osetrin

Kantowski-Sachs perfect fluid cosmological model is explored in modified gravity with functional form $f(R, T)$=$f_1(R)$+$f_2(T)$ where $R$ is Ricci scalar, and $T$ is the trace of the energy-momentum tensor. With this functional form,…

General Relativity and Quantum Cosmology · Physics 2023-04-26 T. Vinutha , K. Niharika , K. Sri Kavya

A general treatment of vorticity-free, perfect fluid perturbations of Kantowski-Sachs models with a positive cosmological constant are considered within the framework of the 1+1+2 covariant decomposition of spacetime. The dynamics is…

General Relativity and Quantum Cosmology · Physics 2015-12-08 Zoltán Keresztes , Mats Forsberg , Michael Bradley , Peter K. S. Dunsby , László Á. Gergely

In this paper, by analyzing the instability against spatially homogeneous and anisotropic perturbations of the Kantowski-Sachs-type during different cosmological epoch, we show that it is a theoretical consequence of the general relativity…

Astrophysics · Physics 2009-11-10 Xin-zhou Li , Jian-gang Hao
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