Results 21 to 30 of about 1,695 (179)
AbstractToday Noether's principal theorem occupies a prominent place in theoretical physics, though for a long time its significance was largely overlooked. Even now, relatively few physicists realize that Emmy Noether's original paper from 1918 contains two fundamental theorems.
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Electric–magnetic symmetry and Noether's theorem
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 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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Noether's theorem and gauge transformations. Application to the bosonic string and CP(2,n-1) model [PDF]
New results on the theory of constrained systems are applied to characterize the generators of Noethers symmetry transformations. As a byproduct, an algorithm to construct gauge transformations in Hamiltonian formalism is derived.
C. Batlle +4 more
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On the structure of conservation laws of (3+1)-dimensional wave equation
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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Extensions of Noether's Second Theorem: from continuous to discrete systems [PDF]
A simple local proof of Noether's Second Theorem is given. This proof immediately leads to a generalization of the theorem, yielding conservation laws and/or explicit relationships between the Euler--Lagrange equations of any variational problem whose ...
Dorodnitsyn V. +2 more
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Noether theorem for μ-symmetries [PDF]
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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Linear Time-Dependent Invariants for Scalar Fields and Noether's Theorem [PDF]
The infinite number of time-dependent linear in field and conjugated momenta invariants is derived for the scalar field using the Noether's theorem procedure.Comment: LaTeX, 6 pages, preprint of Instituto de Ciencias Nucleares, UNAM, Departamento de F ...
Castaños, O. +2 more
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Fractional derivative generalization of Noether’s theorem
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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Calculation of the angular momentum of an electromagnetic field inside a waveguide with absolutely conducting walls: ab initio [PDF]
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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