Results 11 to 20 of about 315 (137)
Noether’s theorem for Herglotz type variational problems utilizing complex fractional derivatives [PDF]
Theoretical and Applied Mechanics, 2021 This is a review article which elaborates the results presented in [1], where the variational principle of Herglotz type with a Lagrangian that depends on fractional derivatives of both real and complex orders is formulated and the invariance of this ...
Janev Marko +2 more
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A new perspective on spacetime 4D rotations and the SO(4) transformation group
Results in Physics, 2019 In quantum field theory, every conservation law is enforced by adequate symmetries. The Lorentz group, which represents two continuous symmetries: rotations in 3D Euclidean space and Lorentz boosts, generates conservation of the angular momentum tensor ...
Mikołaj Myszkowski
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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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The Concept of Symmetry and the Theory of Perception
Frontiers in Computational Neuroscience, 2021 Perceptual constancy refers to the fact that the perceived geometrical and physical characteristics of objects remain constant despite transformations of the objects such as rigid motion.
Zygmunt Pizlo, J. Acacio de Barros
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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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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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