Results 21 to 30 of about 8,019 (262)
Construction of energy–momentum tensor of gravitation [PDF]
International Journal of Geometric Methods in Modern Physics, 2016 We construct the gravitational energy–momentum tensor in general relativity through the Noether theorem. In particular, we explicitly demonstrate that the constructed quantity can vary as a tensor under the general coordinate transformation. Furthermore, we verify that the energy–momentum conservation is satisfied because one of the two indices of the
Bamba, Kazuharu, Shimizu, Katsutaro
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To Conserve, or Not to Conserve: A Review of Nonconservative Theories of Gravity
Universe, 2021 Apart from the familiar structure firmly-rooted in the general relativistic field equations where the energy–momentum tensor has a null divergence i.e., it conserves, there exists a considerable number of extended theories of gravity allowing departures ...
Hermano Velten, Thiago R. P. Caramês
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The energy–momentum tensor(s) in classical gauge theories
Nuclear Physics B, 2016 We give an introduction to, and review of, the energy–momentum tensors in classical gauge field theories in Minkowski space, and to some extent also in curved space–time.
Daniel N. Blaschke +3 more
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ENERGY-MOMENTUM TENSORS WITH WORLDLINE NUMERICS [PDF]
International Journal of Modern Physics: Conference Series, 2012 We apply the worldline formalism and its numerical Monte-Carlo approach to computations of fluctuation induced energy-momentum tensors. For the case of a fluctuating Dirichlet scalar, we derive explicit worldline expressions for the components of the canonical energy-momentum tensor that are straightforwardly accessible to partly analytical and ...
Schäfer, Marco +2 more
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From Heisenberg–Euler Lagrangian to the discovery of Chromomagnetic Gluon Condensation
European Physical Journal C: Particles and Fields, 2020 I reexamine the phenomena of the chromomagnetic gluon condensation in Yang–Mills theory. The extension of the Heisenberg–Euler Lagrangian to the Yang–Mills theory allows to calculate the effective action, the energy-momentum tensor and demonstrate that ...
George Savvidy
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Minkowski and Galilei/Newton Fluid Dynamics: A Geometric 3 + 1 Spacetime Perspective
Fluids, 2018 A kinetic theory of classical particles serves as a unified basis for developing a geometric 3 + 1 spacetime perspective on fluid dynamics capable of embracing both Minkowski and Galilei/Newton spacetimes. Parallel treatment of these cases on as common a
Christian Cardall
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Vacuum polarization of scalar field on Lie groups with Bi-invariant metric [PDF]
Компьютерные исследования и моделирование, 2015 We consider vacuum polarization of a scalar field on the Lie groups with a bi-invariant metric of Robertson-Walker type. Using the method of orbits we found expression for the vacuum expectation values of the energy-momentum tensor of the scalar field ...
Alexander Igorevich Breev +1 more
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Energy–momentum tensor on foliations
Journal of Geometry and Physics, 2007 In this paper, we give a new lower bound for the eigenvalues of the Dirac operator on a compact spin manifold. This estimate is motivated by the fact that in its limiting case a skew-symmetric tensor (see Equation \eqref{eq:16}) appears that can be identified geometrically with the O'Neill tensor of a Riemannian flow, carrying a transversal parallel ...
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The gauge-invariant canonical energy-momentum tensor
EPJ Web of Conferences, 2016 The canonical energy-momentum tensor is often considered as a purely academic object because of its gauge dependence. However, it has recently been realized that canonical quantities can in fact be defined in a gauge-invariant way provided that strict ...
Lorcé Cédric
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Monopole and quadrupole contributions to the angular momentum density
Physics Letters B, 2019 The energy-momentum tensor form factors contain a wealth of information about the nucleon. It is insightful to visualize this information in terms of 3D or 2D densities related by Fourier transformations to the form factors. The densities associated with
Peter Schweitzer, Kemal Tezgin
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