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We can solve the Wheeler-DeWitt equation of the enlarged Bianchi I as inhomogeneous type universe with static restriction which had been derived by previous paper. We consider the commutation relation between the static restriction and the…

General Relativity and Quantum Cosmology · Physics 2008-11-28 Shintaro Sawayama

We study the role of non-perturbative quantum gravity effects in the Ekpyrotic/Cyclic model using the effective framework of loop quantum cosmology in the presence of anisotropies. We show that quantum geometric modifications to the…

General Relativity and Quantum Cosmology · Physics 2010-04-30 Thomas Cailleteau , Parampreet Singh , Kevin Vandersloot

In the particular configuration of the scalar field K-essence in the Wheeler-DeWitt quantum equation, for some age in the Bianchi type I anisotropic cosmological model, a fractional differential equation for the scalar field arises…

General Relativity and Quantum Cosmology · Physics 2023-11-09 J. Socorro , J. Juan Rosales , L. Toledo Sesma

In this work, the quantization of the most general Bianchi Type I geometry, with and without a cosmological constant, is considered. In the spirit of identifying and subsequently removing as many gauge degrees of freedom as possible, a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 T. Christodoulakis , T. Gakis , G. O. Papadopoulos

The present study deals with spatially homogeneous and totally anisotropic locally rotationally symmetric (LRS) Bianchi type I cosmological model with variable $G$ and $\Lambda$ in presence of imperfect fluid. To get the deterministic model…

General Physics · Physics 2012-01-17 Anil Kumar Yadav , Anirudh Pradhan , Ajay Kumar Singh

We derive the metric for a Bianchi type I space-time with energy density that is dominated by that of a perfect fluid with equation of state $p=w\rho$ and whose anisotropy is seeded by a fixed norm spacelike vector field. We solve for the…

General Relativity and Quantum Cosmology · Physics 2008-05-21 Timothy R. Dulaney , Moira I. Gresham

We continue our analysis of a quantum cosmology model describing a flat Friedmann--Lema\^itre--Robertson--Walker universe filled with a (free) massless scalar field and an arbitrary perfect fluid. For positive energy density in the scalar…

General Relativity and Quantum Cosmology · Physics 2022-04-08 Steffen Gielen , Lucía Menéndez-Pidal

The equations governing the evolution of non-minimally coupled scalar matter and the scale factor of a Robertson-Walker universe are derived from a minisuperspace action. As for the minimally coupled case, it is shown that the entire…

General Relativity and Quantum Cosmology · Physics 2009-10-31 G. L. Alberghi , R. Casadio , A. Gruppuso

We present and expand the simplest possible quantum cosmological bouncing model already discussed in previous works: the trajectory formulation of quantum mechanics applied to cosmology (through the Wheeler-De Witt equation) in the FLRW…

General Relativity and Quantum Cosmology · Physics 2016-07-20 Patrick Peter , Sandro D. P. Vitenti

Equations for 16-component vector-bispinor field, originated from Rarita-Schwinger Lagrangian for spin 3/2 field extended to Riemannian space-time are investigated. Additional general covariant constrains for the field are produced, which…

Mathematical Physics · Physics 2011-09-20 V. M. Red'kov

The quantum evolution equation of Loop Quantum Cosmology (LQC) -- the quantum Hamiltonian constraint -- is a difference equation. We relate the LQC constraint equation in vacuum Bianchi I separable (locally rotationally symmetric) models…

General Relativity and Quantum Cosmology · Physics 2013-01-25 Christine C. Dantas

Here, we have investigated the interaction of Bianchi type I anisotropic cloud string cosmological model universe with electromagnetic field in the context of general relativity. In this paper, the energy momentum tensor is assumed to be…

General Relativity and Quantum Cosmology · Physics 2019-10-21 Kangujam Priyokumar Singh , Mahbubur Rahman Mollah , Rajshekhar Roy Baruah , Meher Daimary

We study Dirac spinors in Bianchi type-I cosmological models, within the framework of torsional $f(R)$-gravity. We find four types of results: the resulting dynamic behavior of the universe depends on the particular choice of function…

General Relativity and Quantum Cosmology · Physics 2011-11-14 Stefano Vignolo , Luca Fabbri , Roberto Cianci

Self-consistent system of nonlinear spinor field and Bianchi I (BI) gravitational one with time dependent gravitational constant ($G$) and cosmological constant ($\Lambda$) has been studied. The initial and the asymptotic behaviors of the…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Bijan Saha

The dynamics and evolution of Bianchi type I space-times is considered in the framework of the four-dimensional truncation of a reduced theory obtained from the N=2,D=5 supergravity. The general solution of the gravitational field equations…

High Energy Physics - Theory · Physics 2009-10-31 Chiang-Mei Chen , T. Harko , M. K. Mak

This paper is devoted to study Bianchi type I cosmological model in Brans-Dicke theory with self-interacting potential by using perfect, anisotropic and magnetized anisotropic fluids. We assume that the expansion scalar is proportional to…

General Relativity and Quantum Cosmology · Physics 2015-06-04 M. Sharif , Saira Waheed

In this article we compute the density of scalar and Dirac particles created by a cosmological anisotropic Bianchi type I universe in the presence of a time varying electric field. We show that the particle distribution becomes thermal when…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Victor M. Villalba , Walter Greiner

A twisted ${\mathcal C}^\star $- algebra of the extended (noncommutative) Heisenberg-Weyl group has been constructed which takes into account the Uncertainty Principle for coordinates in the Planck length regime. This general construction…

General Relativity and Quantum Cosmology · Physics 2014-04-30 Marcos Rosenbaum , J. David Vergara , Román Juárez , A. A. Minzoni

Due to the numerical complexities of studying evolution in an anisotropic quantum spacetime, in comparison to the isotropic models, the physics of loop quantized anisotropic models has remained largely unexplored. In particular, robustness…

General Relativity and Quantum Cosmology · Physics 2017-04-14 Peter Diener , Anton Joe , Miguel Megevand , Parampreet Singh

Despite having a reasonably successful account of accelerated cosmology, understanding the early evolution of Universe has always been difficult for mankind. Our promising strategy is based on a novel class of symmetric teleparallel…

General Relativity and Quantum Cosmology · Physics 2022-09-12 L. Anjana Devi , S. Surendra Singh , Leishingam Kumrah , Md Khurshid Alam