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Related papers: Nonlinear Spinor Fields in Bianchi type-III spacet…

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The study of a self-consistent system of interacting spinor and scalar fields within the scope of a Bianchi type I (BI) gravitational field in presence of a viscous fluid and $\Lambda$ term has been carried out. The system of equations…

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

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

In homogeneous and isotropic loop quantum cosmology, gravity can behave repulsively at Planckian energy densities leading to the replacement of the big bang singularity with a big bounce. Yet in any bouncing scenario it is important to…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Dah-Wei Chiou , Kevin Vandersloot

It is shown that models of elementary particles in classical general relativity (geons) will naturally have the transformation properties of a spinor if the spacetime manifold is not time orientable. From a purely pragmatic interpretation…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Mark J. Hadley

The microlocal space-time of extended hadrons, considered to be anisotropic is specified here as a special Finsler space. For this space the classical field equation is obtained from a property of the field on the neighbouring points of the…

High Energy Physics - Theory · Physics 2007-05-23 S. S. De

We analyse quantised scalar, spinor and photon fields in a mechanically rigid cavity that is accelerated in Minkowski spacetime, in a recently-introduced perturbative small acceleration formalism that allows the velocities to become…

Quantum Physics · Physics 2013-09-17 Nicolai Friis , Antony R. Lee , Jorma Louko

The paper deals with Bianchi type V Universe, which has dynamical energy density. We consider Bianchi type V space-time, introducing three different skewness parameters along spatial directions to quantify the deviation of pressure from…

General Physics · Physics 2015-03-17 Anil Kumar Yadav

Modular and quasimodular forms have played an important role in gravity and string theory. Eisenstein series have appeared systematically in the determination of spectrums and partition functions, in the description of non-perturbative…

Mathematical Physics · Physics 2012-06-05 P. Marios Petropoulos , Pierre Vanhove

We scrutinize the overall structure of the space of cosmological models of Bianchi type I-VII$_h$ that contain a free massless scalar field, with a spatially homogeneous gradient $\nabla_\mu \varphi$ that generally breaks isotropy, in…

General Relativity and Quantum Cosmology · Physics 2019-11-05 Mikjel Thorsrud

Bianchi type I magnetized cosmological models in the presence of a bulk viscous fluid are investigated. The source of the magnetic field is due to an electric current produced along x-axis. The distribution consists of an electrically…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Anirudh Pradhan , Om Prakash Pandey

We use a perturbative method to evaluate the effective action of a free scalar field propagating in the Bianchi type I spacetime with large space anisotropy. The zeta- function regularization method is used to evaluate the action to the…

High Energy Physics - Theory · Physics 2009-11-07 Wung-Hong Huang

In this paper, we investigate a non-canonical scalar field model in the background dynamics of anisotropic Locally Rotationally Symmetric (LRS) Bianchi type I universe where gravity is coupled minimally to scalar field which is taken as…

General Relativity and Quantum Cosmology · Physics 2023-11-17 Sujoy Bhanja , Goutam Mandal , Abdulla Al Mamon , Sujay Kr. Biswas

We examine whether an extended scenario of a two-scalar-field model, in which a mixed kinetic term of canonical and phantom scalar fields is involved, admits the Bianchi type I metric, which is homogeneous but anisotropic spacetime, as its…

General Relativity and Quantum Cosmology · Physics 2017-02-28 Tuan Q. Do , Sonnet Hung Q. Nguyen

We study a complex Dirac field in the chiral representation minimally coupled to gravity in 3+1 dimensions in the context of Einstein-Cartan theory. Generically the matter content gravitates in two different ways: On the one hand, the…

General Relativity and Quantum Cosmology · Physics 2015-03-12 Adolfo Toloza

In the scope of the nonlinear massive gravity, we study fixed points of evolution equations for a Bianchi type--I universe. We find a new attractor solution with non-vanishing anisotropy, on which the physical metric is isotropic but the…

High Energy Physics - Theory · Physics 2012-10-17 A. Emir Gumrukcuoglu , Chunshan Lin , Shinji Mukohyama

A spatially homogeneous Bianchi type VI0 model containing a viscous fluid in the presence of an axial magnetic field has been studied. A barotropic equation of state together with a pair of linear relations among the square root of matter…

General Relativity and Quantum Cosmology · Physics 2021-05-18 Marcelo Byrro Ribeiro , Abhik Kumar Sanyal

We investigate a corner of the Bianchi models that has not received much attention: "extended FLRW models" (eFLRW) defined as a cosmological model with underlying anisotropic Bianchi geometry that nevertheless expands isotropically and can…

General Relativity and Quantum Cosmology · Physics 2020-02-21 Mikjel Thorsrud , Ben D. Normann , Thiago S. Pereira

In this paper, Dirac`s equation in anisotropic Bianchi-type-I background spacetimes is treated w.r.t. orthonormal frames. By specializing to the massless spinor case and metrics with power-law scale factors and planar symmetry, an…

Mathematical Physics · Physics 2023-01-02 Matthias Wollensak

We study a class of homogeneous but anisotropic cosmologies within the family of shift-symmetric Horndeski theories, where the scalar field features an inhomogeneous profile but it preserves a translational symmetry that is realised as a…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-13 J. Bayron Orjuela-Quintana , Jose Beltrán Jiménez

We review a technique for solving a class of classical linear partial differential systems of relevance to physics in Minkowski spacetime. All the equations are amenable to analysis in terms of complex solutions in the kernel of the scalar…

General Relativity and Quantum Cosmology · Physics 2022-02-23 Robin W. Tucker , Timothy J. Walton