Results 11 to 20 of about 8,019 (262)
Atti della Accademia Peloritana dei Pericolanti : Classe di Scienze Fisiche, Matematiche e Naturali, 2023 Creating a modified Belinfante/Rosenfeld procedure, Mathisson-Papapetrou-like equations are derived by which a comparison of General-Covariant Continuum Physics (GCCP) with General Relativity Theory (GRT) becomes possible.
Wolfgang Muschik
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On Sugawara construction on celestial sphere
Journal of High Energy Physics, 2020 Conformally soft gluons are conserved currents of the Celestial Conformal Field Theory (CCFT) and generate a Kac-Moody algebra. We study celestial amplitudes of Yang-Mills theory, which are Mellin transforms of gluon amplitudes and take the double soft ...
Wei Fan +3 more
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Covariant Derivative of Fermions and All That
Universe, 2022 We present detailed pedagogical derivation of covariant derivative of fermions and some related expressions, including commutator of covariant derivatives and energy-momentum tensor of a free Dirac field.
Ilya L. Shapiro
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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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On the energy–momentum tensor [PDF]
Journal of Physics A: Mathematical and General, 2004 We clarify the relation among canonical, metric and Belinfante's energy-momentum tensors for general tensor field theories. For any tensor field T, we define a new tensor field $\til {\bm T}$, in terms of which the Belinfante tensor is readily computed.
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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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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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The electromagnetic energy momentum tensor [PDF]
Journal of Physics A: Mathematical and General, 2002 We clarify the relation between canonical and metric energy-momentum tensors. In particular, we show that a natural definition arises from Noether's Theorem which directly leads to a symmetric and gauge invariant tensor for electromagnetic field theories on an arbitrary space-time of any dimension.
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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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Energy-Momentum Tensor Form Factors in QED
SciPost Physics Proceedings, 2022 We present the results for the Energy-Momentum Tensor (EMT) form factor D(t) at oneloop accuracy in quantum electrodynamics for an electron state. We report the the results in the case of both zero and nonzero photon mass.
Simone Rodini, Andreas Metz, Barbara Pasquini
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