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Related papers: Zero-size objects in Riemann-Cartan spacetime

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Dirac equation is written in a non-Riemannian spacetime with torsion and non-metricity by lifting the connection from the tangent bundle to the spinor bundle over spacetime. Foldy-Wouthuysen transformation of the Dirac equation in a…

General Relativity and Quantum Cosmology · Physics 2009-11-07 M. Adak , T. Dereli , L. H. Ryder

We derive and discus the equations of motion for spinless matter: relativistic spinless scalar fields, particles and fluids in the recently proposed by A. Saa model of gravity with covariantly constant volume with respect to the transposed…

General Relativity and Quantum Cosmology · Physics 2015-06-25 P. P. Fiziev

We analyse the kinematics of cosmological spacetimes with nonzero torsion, in the framework of the classical Einstein-Cartan gravity. After a brief introduction to the basic features of spaces with non-vanishing torsion, we consider a…

General Relativity and Quantum Cosmology · Physics 2017-05-17 Klaountia Pasmatsiou , Christos G. Tsagas , John D. Barrow

We derive the general solution to the coupled Einstein and Dirac field equations in static and hyperplane-symmetric spacetime of arbitrary dimension including a cosmological constant of either sign. As a result, only a massful Dirac field…

General Relativity and Quantum Cosmology · Physics 2024-10-08 John Schliemann , Tim Sonnleitner

We discuss the relation of the Kerr-Newman spinning particle to the Dirac electron and show that the Dirac equation may naturally be incorporated into Kerr-Schild formalism as a master equation controlling the Kerr-Newman geometry. As a…

High Energy Physics - Theory · Physics 2008-11-26 Alexander Burinskii

We study the effects of the spatial curvature on the classical and quantum string dynamics. We find the general solution of the circular string motion in static Robertson-Walker spacetimes with closed or open sections. This is given closely…

High Energy Physics - Theory · Physics 2010-11-01 A. L. Larsen , N. Sanchez

The dynamics of brane-like extended objects in spacetimes with torsion is derived from the conservation equations of stress-energy and spin tensors. Thus obtained world-sheet equations are applied to macroscopic test membranes made of…

General Relativity and Quantum Cosmology · Physics 2010-04-07 Milovan Vasilic , Marko Vojinovic

We study massless Duffin-Kemmer-Petiau (DKP) fields in the context of Einstein-Cartan gravitation theory, interacting via minimal coupling procedure. In the case of an identically vanishing torsion (Riemannian space-times) we show that…

General Relativity and Quantum Cosmology · Physics 2009-11-07 R. Casana , V. Ya. Fainberg , B. M. Pimentel , J. T. Lunardi , R. G. Teixeira

In a sense of deformation quantization, noncommutative (NC) geometry introduces a quantum structure of spacetime. Using the twist-deformation formalism, we show that the dynamical effects of spacetime noncommutativity can amount to a…

High Energy Physics - Theory · Physics 2025-07-17 Dušan Đorđević , Dragoljub Gočanin

The Poincare and Poincare-Weyl gauge theories of gravitation with Lagrangians quadratic on curvature and torsion in post-Riemannian spaces with the Dirac scalar field is discussed in a historical aspect. The various hypothesizes concerning…

General Relativity and Quantum Cosmology · Physics 2016-11-01 O. V. Babourova , B. N. Frolov , P. E. Kudlaev , E. V. Romanova

The gravitational effects in the relativistic quantum mechanics are investigated. The exact Foldy-Wouthuysen transformation is constructed for the Dirac particle coupled to the static spacetime metric. As a direct application, we analyze…

General Relativity and Quantum Cosmology · Physics 2011-08-17 Yuri N. Obukhov

Self-gravitating horizonless ultra-compact objects that possess light rings have attracted the attention of physicists and mathematicians in recent years. In the present compact paper we raise the following physically interesting question:…

General Relativity and Quantum Cosmology · Physics 2025-02-05 Shahar Hod

This article investigates some solutions of the time-dependent free Dirac equation. Visualizations of these solutions immediately reveal strange phenomena that are caused by the interference of positive- and negative-energy waves. The…

Quantum Physics · Physics 2007-05-23 Bernd Thaller

There are constructed exact solutions of the quantum-mechanical Dirac equation for a spin S=1/2 particle in the space of constant positive curvature, spherical Riemann space, in presence of an external magnetic field, analogue of the…

Mathematical Physics · Physics 2010-05-21 E. M. Ovsiyuk , V. V. Kisel , V. M. Red'kov

The relativistic spinning particle model, proposed in [3,4], is analyzed in a Hamiltonian framework. The spin is simulated by extending the configuration space by introducing a light-like four vector degree of freedom. The model is heavily…

High Energy Physics - Theory · Physics 2009-11-06 Sudipta Das , Subir Ghosh

By requiring unambiguous symmetric quantization leading to the Dirac equation in a curved space, we obtain a special representation of the spin connections in terms of the Dirac gamma matrices and their space-time derivatives. We also…

High Energy Physics - Theory · Physics 2015-10-22 A. D. Alhaidari , A. Jellal

The dynamical realisation of the equation of state $p +\rho =0$ is studied. A non-pathological dynamics for the perturbations of such a system mimicking a dynamical cosmological constant (DCC) requires to go beyond the perfect fluid…

High Energy Physics - Theory · Physics 2025-03-06 Giuseppe di Donato , Luigi Pilo

We extend the fully non-linear and exact cosmological perturbation equations in a Friedmann background universe to include the background curvature. The perturbation equations are presented in a gauge ready form, so any temporal gauge…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Hyerim Noh

Einstein-Cartan theory is formulated in (1+2)-dimensions using the algebra of exterior differential forms. A Dirac spinor is coupled to gravity and the field equations are obtained by a variational principle. The space-time torsion is found…

General Relativity and Quantum Cosmology · Physics 2010-02-05 T. Dereli , N. Ozdemir , O. Sert

In our previous paper [Phys. Rev. D 89 (2014) 124029], cited as [1], we attempted to find Robinson-Trautman-type solutions of Einstein's equations representing gyratonic sources (matter field in the form of an aligned null fluid, or…

General Relativity and Quantum Cosmology · Physics 2019-02-13 Jiri Podolsky , Robert Svarc
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