Results 21 to 30 of about 232 (162)
Electric–magnetic symmetry and Noether's theorem
New Journal of Physics, 2012 In the absence of charges, Maxwell's equations are highly symmetrical. In particular, they place the electric and magnetic fields on equal footing.
Robert P Cameron, Stephen M Barnett
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On the structure of conservation laws of (3+1)-dimensional wave equation
Arab Journal of Mathematical Sciences, 2018 In this paper, a (3+1)-dimensional wave equation is studied from the point of view of Lie’s theory in partial differential equations including conservation laws.
S. Reza Hejazi, Elham Lashkarian
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Revista Integración, 2023 The optimal generating operators for the relativistic fluid sphere equation have been derived. We have characterized all invariant solutions of this equation using these operators.
Yeisson Alexis Acevedo Agudelo +3 more
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Energy in gravitation and Noether’s theorems* [PDF]
Journal of Physics A: Mathematical and Theoretical, 2019 I exhibit the conflicting roles of Noether’s two great theorems in defining conserved quantities, especially energy in general relativity and its extensions: it is the breaking of coordinate invariance through boundary conditions that removes the barrier her second theorem otherwise poses to the applicability of her first.
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Fractional derivative generalization of Noether’s theorem
Open Mathematics, 2015 The symmetry of the Bagley–Torvik equation is investigated by using the Lie group analysis method. The Bagley–Torvik equation in the sense of the Riemann–Liouville derivatives is considered.
Khorshidi Maryam +2 more
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Variational Problems with Partial Fractional Derivative: Optimal Conditions and Noether’s Theorem
Journal of Function Spaces, 2018 In this paper, the necessary and sufficient conditions of optimality for variational problems with Caputo partial fractional derivative are established. Fractional Euler-Lagrange equations are obtained.
Jun Jiang, Yuqiang Feng, Shougui Li
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Calculation of the angular momentum of an electromagnetic field inside a waveguide with absolutely conducting walls: ab initio [PDF]
Компьютерная оптика, 2018 In this paper, explicit expressions for the momentum and angular momentum from the Noether's theorem (ab initio) are obtained. These expressions contain squared modules of the coefficients of a guided mode expansion, weighted by the phase singularity ...
Sergey Kharitonov +2 more
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Anomalies in quantum field theories
Vojnotehnički Glasnik, 2023 Introduction/purpose: Noether’s theorem connects symmetry of the Lagrangian to conserved quantities. Quantum effects cancel the conserved quantities. Methods: Triangle diagram, Path integral, Pauli-Villars regularisation. Results: Quantum effects that
Nicola Fabiano
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Noether theorem for μ-symmetries [PDF]
Journal of Physics A: Mathematical and Theoretical, 2007 We give a version of Noether theorem adapted to the framework of mu-symmetries; this extends to such case recent work by Muriel, Romero and Olver in the framework of lambda-symmetries, and connects mu-symmetries of a Lagrangian to a suitably modified conservation law. In some cases this "mu-conservation law'' actually reduces to a standard one; we also
G. Cicogna, G. Gaeta
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Noether theorems and quantum anomalies [PDF]
Doklady Mathematics, 2017 In this communication, we show that both infinite-dimensional versions of Noether's theorems, and the explanation of quantum anomalies can be obtained using similar formulas for the derivatives of functions whose values are measures (Smolyanov and von Weizsaecker, 1995) or pseudomeasures (Gough, Ratiu and Smolyanov, 2015). In particular, we improve son
Gough, J. +2 more
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