Results 21 to 30 of about 5,915,931 (293)
On Equivalence of Definition of the Energy-Momentum Tensor in General Relativity and Field Theory [PDF]
Iranian Journal of Astronomy and AstrophysicsThis work investigates a fundamental pedagogical question concerning the definition of the energy-momentum tensor in theoretical physics. Students learn the definition of energy-momentum tensor in the field theory and on the other hand a different ...
Sohrab Rahvar
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Energy-momentum tensor for the gravitational field [PDF]
Physical Review D, 1999 The search for the gravitational energy-momentum tensor is often qualified as an attempt of looking for ``the right answer to the wrong question''. This position does not seem convincing to us. We think that we have found the right answer to the properly formulated question.
Babak, S V, Grishchuk, L P
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Higher order gravities and the Strong Equivalence Principle
Journal of High Energy Physics, 2017 We show that, in all metric theories of gravity with a general covariant action, gravity couples to the gravitational energy-momentum tensor in the same way it couples to the matter energy-momentum tensor order by order in the weak field approximation ...
Tomás Ortín
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Mass-Energy-Momentum: Only there because of Spacetime? [PDF]
, 2010 I describe how relativistic field theory generalises the paradigm property of material systems, the possession of mass, to the requirement that they have a mass-energy-momentum density tensor associated with them.
Lehmkuhl, D +2 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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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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Hilbert's energy-momentum tensor extended [PDF]
, 2022 A variational derivative of a Lagrangian with regard to the metric tensor is used in classical field models to define Hilbert's energy-momentum tensor for a matter field.
Itin, Yakov
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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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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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Energy-momentum tensor for cosmological perturbations [PDF]
Physical Review D, 1997 We study the effective energy-momentum tensor (EMT) for cosmological perturbations and formulate the gravitational back-reaction problem in a gauge invariant manner. We analyze the explicit expressions for the EMT in the cases of scalar metric fluctuations and of gravitational waves and derive the resulting equations of state.
Abramo, L. R. +2 more
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