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Related papers: Nonlinear Spinor Fields in Bianchi type-I spacetim…

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Within the scope of a spherically symmetric space-time we study the role of a nonlinear spinor field in the formation of different configurations with spherical symmetries. The presence of the non-diagonal components of energy-momentum…

General Relativity and Quantum Cosmology · Physics 2018-12-31 Bijan Saha

Different characteristic of matter influencing the evolution of the Universe has been simulated by means of a nonlinear spinor field. Exploiting the spinor description of perfect fluid and dark energy evolution of the Universe given by an…

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

In this study, we examine the role of a scalar field in the evolution of the Universe within the framework of a Bianchi type-I cosmological model with Lyra's geometry. Previous research has explored the nonlinear spinor field in various…

General Relativity and Quantum Cosmology · Physics 2026-03-20 Evgeny Petuhov , Bijan Saha

Self-consistent solutions to the nonlinear spinor field equations in General Relativity has been studied for the case of Bianchi type-I (B-I) space-time. It has been shown that, for some special type of nonliearity the model provides…

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

Within the scope of a static cylindrically symmetric space-time we study the behavior of a nonlinear spinor field that depends on time and radial coordinates. It is found that the presence of nontrivial non-diagonal components of the…

General Relativity and Quantum Cosmology · Physics 2022-09-21 Bijan Saha

This study constrains the cosmological parameters within the scope of a spherically symmetric FLRW cosmological model, the role of a nonlinear spinor field in the universe's evolution. To test this approach, we incorporate the recent Cosmic…

General Physics · Physics 2026-05-18 Bijan Saha , Mahendra Goray

Within the scope of a LRS Bianchi type-I cosmological model we study the role of the nonlinear spinor field in the evolution of the Universe. In doing so we consider a polynomial type of nonlinearity that describes different stages of the…

General Relativity and Quantum Cosmology · Physics 2017-11-02 Bijan Saha , Victor S. Rikhvitsky

We consider a system of nonlinear spinor and a Bianchi type I gravitational fields in presence of viscous fluid. The nonlinear term in the spinor field Lagrangian is chosen to be $\lambda F$, with $\lambda$ being a self-coupling constant…

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

Self-consistent system of spinor, scalar and BI gravitational fields is considered. Exact solutions to the field equations in terms of volume scale of the BI metric are obtained. Einstein field equations in account of the cosmological…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Bijan Saha , Todor Boyadjiev

Within the scope of anisotropic non-diagonal Bianchi type-II, VIII and IX spacetime it is shown that the off-diagonal components of the corresponding metric impose severe restrictions on the components of the energy momentum tensor in…

General Relativity and Quantum Cosmology · Physics 2020-07-17 Bijan Saha

Self-consistent system of spinor, scalar and BI gravitational fields in presence of magneto-fluid and $\Lambda$-term is considered. Assuming that the expansion of the BI universe is proportional to the $\sigma_1^1$ component of the shear…

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

A self-consistent system of interaction nonlinear spinor and scalar fields within the scope of a BI cosmological model filled with perfect fluid is considered. The role of spinor field in the evolution of the Universe is studied. It is…

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

Within the scope of an anisotropic Bianchi type-V cosmological model we have studied the evolution of the universe. The assumption of a diagonal energy-momentum tensor leads to some severe restriction on the metric functions, which on its…

General Physics · Physics 2015-05-01 Bijan Saha

Self-consistent solutions to the spinor, scalar and BI gravitational field equations are obtained. The problems of initial singularity and asymptotically isotropization process of the initially anisotropic space-time are studied. It is also…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Bijan Saha

Within the framework of Bianchi type-II (BII) cosmological model the behavior of matter distribution has been considered. It is shown that the non-zero off-diagonal component of Einstein tensor implies some severe restriction on the choice…

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

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

Within the scope of Bianchi type VI (BVI) model the self-consistent system of nonlinear spinor and gravitational fields is considered. Exact self-consistent solutions to the spinor and gravitational field equations are obtained for some…

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

We consider a system of nonlinear spinor and scalar fields with minimal coupling in general relativity. The nonlinearity in the spinor field Lagrangian is given by an arbitrary function of the invariants generated from the bilinear spinor…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Bijan Saha , G. N. Shikin

F-essence is a generalization of the usual Dirac model with the nonstandard kinetic term. In this paper, we introduce a new model of spinor cosmology containing both Ricci scalar and the non minimally coupled spinor fields in its action. We…

General Physics · Physics 2012-04-09 Mubasher Jamil , D. Momeni , N. S. Serikbayev , R. Myrzakulov

Different characteristic of matter influencing the evolution of the Universe has been simulated by means of a nonlinear spinor field. Using the nonlinear spinor field corresponding to different types of perfect fluid or dark energy as a…

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