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arXiv · 2605.15148

Noether symmetries and conservation laws of a class of time-dependent multidimensional nonlinear wave equations

F. Güngör·C. Özemir
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Abstract

Conservation laws of a class of time-dependent damped nonlinear multidimensional wave equations are derived by Noether's theorem. For arbitrary nonzero damping coefficient and nonlinear interaction term, its infinitesimal variational symmetries span a Euclidean algebra $\euclid(n)$ of space translations and rotations. They produce conservation of linear and angular momentums. For some specific forms of these two terms symmetry algebra is enlarged to a subalgebra of the conformal algebra $\conf(1,n)$ and in this case more interesting conservation laws are found.

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F. Güngör, C. Özemir. 2026-05-14. Noether symmetries and conservation laws of a class of time-dependent multidimensional nonlinear wave equations. https://arxiv.org/abs/2605.15148

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