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Related papers: Nonlinear Spinor Fields in Bianchi type-VI spaceti…

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This paper delves into the deformation of spinor structures within nontrivial topologies and their physical implications. The deformation is modeled by introducing real functions that modify the standard spinor dynamics, leading to distinct…

Mathematical Physics · Physics 2025-02-19 J. M. Hoff da Silva , R. T. Cavalcanti , G. M. Caires da Rocha

A model for an anisotropic Bianchi type VI universe in a Scale Covariant theory of gravitation (Canuto et al. 1977) is analyzed. A finite singularity is found in the model at the initial time $t=0$. All the physical parameters are studied…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Mohd. Zeyauddin , Bijan Saha

Quasi-constant external fields in nonlinear electromagnetism generate a contribution to the energy-momentum tensor with the form of dark energy. To provide a thorough understanding of the origin and strength of the effects, we undertake a…

High Energy Physics - Theory · Physics 2010-04-14 Lance Labun , Johann Rafelski

It is shown that the existence of the cosmic kinematic fast dynamos in Bianchi type IX rotating cosmological models, faces severe difficulties, due to the fact that in these models rotation increases without bounds, which is strictly…

Astrophysics · Physics 2007-07-23 Garcia de Andrade

Non-linear gravitational clustering in a universe dominated by dark energy, modelled by a `quintessence' scalar field, and cold dark matter with space-time varying mass is studied. Models of this type, where the variable mass is induced by…

Astrophysics · Physics 2009-11-07 S. Matarrese , M. Pietroni , C. Schimd

In this paper we investigate, from the dynamical systems perspective, the evolution of an scalar field with arbitrary potential trapped in a Randall-Sundrum's Braneworld of type 2. We consider an homogeneous but anisotropic Bianchi I (BI)…

General Relativity and Quantum Cosmology · Physics 2012-10-29 Dagoberto Escobar , Carlos R. Fadragas , Genly Leon , Yoelsy Leyva

In this text we introduce the torsion of spinor connections. In terms of the torsion we give conditions on a spinor connection to produce Killing vector fields. We relate the Bianchi type identities for the torsion of spinor connections…

Differential Geometry · Mathematics 2008-12-19 Frank Klinker

We consider a field theoretical model on the noncommutative cylinder which leads to a discrete-time evolution. Its Euclidean version is shown to be equivalent to a model on the complex $q$-plane. We reveal a direct link between the model on…

High Energy Physics - Theory · Physics 2007-05-23 M. Chaichian , A. Demichev , P. Presnajder

The flat anisotropic model of the early Universe is considered. Two interacting scalar fields with special form of potential energy are a source of matter fields. Analytic solutions for inflationary and scalaron stages are found. It is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Vladimir Folomeev

We consider Brans Dicke scalar vector tensor gravity to study an inflationary scenario of the accelerating expansion of the universe for which the anisotropy property occurs. We study both primordial inflation and late inflationary period…

General Relativity and Quantum Cosmology · Physics 2022-09-20 Hossein Ghaffarnejad , Hoda Gholipour

An anisotropic cosmological model with a gauge field, presented by spatially homogeneous SU(2)-symmetric Yang-Mills potentials, is considered. Bianchi-I model with axial symmetry is analyzed; a new exact solution, which describes the early…

General Relativity and Quantum Cosmology · Physics 2025-05-06 Alexander B. Balakin , Gleb B. Kiselev

The nature of cosmological solutions for a homogeneous, anisotropic Universe given by a Bianchi type-I (BI) model in the presence of a Cosmological constant $\Lambda$ is investigated by taking into account dissipative process due to…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Bijan Saha , V. Rikhvitsky

The field equations of Brans-Dicke gravity coupled to a mass-varying vector field are derived. Anisotropic cosmological solutions with a locally rotationally symmetric Bianchi type I metric and time-dependent scalar and electric vector…

General Relativity and Quantum Cosmology · Physics 2014-02-05 Ozgur Akarsu , Tekin Dereli , Neslihan Oflaz

We consider non-minimally coupled (with gravity) scalar field with non-canonical kinetic energy. The form of the kinetic term is of Dirac-Born-Infeld (DBI) form.We study the early evolution of the universe when it is sourced only by the…

Astrophysics · Physics 2015-05-13 A. A. Sen , N. Chandrachani Devi

We investigate a class of models for dark matter and/or negative-pressure, dynamical dark energy consisting of ``spintessence,'' a complex scalar field $\phi$ spinning in a U(1)-symmetric potential $V(\phi)=V(|\phi|)$. As the Universe…

Astrophysics · Physics 2009-11-06 Latham A. Boyle , Robert R. Caldwell , Marc Kamionkowski

Inhomogeneous Bianchi type-I cosmological model with electro-magnetic field based on Lyra geometry is investigated. Using separated method, the Einstein field equations have been solved analytically with the aid of Mathematica programm. A…

General Relativity and Quantum Cosmology · Physics 2013-12-12 Ahmad T Ali , F Rahaman

A formalism for the appearance of dark energy in the matter dominated era, leading to a persistent de Sitter expansion at the late time is proposed. Our framework is a hybrid quintessence model with a non-minimal coupling to the Ricci…

General Relativity and Quantum Cosmology · Physics 2018-11-29 H. Mohseni Sadjadi

Classification of quantum spinor fields according to quantum bilinear covariants is introduced in a context of quantum Clifford algebras on Minkowski spacetime. Once the bilinear covariants are expressed in terms of algebraic spinor fields,…

Mathematical Physics · Physics 2014-10-03 Rafal Ablamowicz , Icaro Gonçalves , Roldao da Rocha

The present study investigates the nature of the field potential via new technique known as reconstruction method for the scalar field potentials. The key point of this technique is the assumption that Hubble parameter is dependent on the…

General Relativity and Quantum Cosmology · Physics 2013-10-14 M. Sharif , Saira Waheed

We study the generalized scalar tensor theory with a potential in the Bianchi type I model by using the ADM formalism. We examine the conditions for the Universe to be in expansion, isotropic and with a positive potential at late time in…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Stephane Fay
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