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Approximate Noether-type symmetries and conservation laws via partial Lagrangians for PDEs with a small parameter

✍ Scribed by A.G. Johnpillai; A.H. Kara; F.M. Mahomed


Publisher
Elsevier Science
Year
2009
Tongue
English
Weight
594 KB
Volume
223
Category
Article
ISSN
0377-0427

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✦ Synopsis


We show how one can construct approximate conservation laws of approximate Euler-type equations via approximate Noethertype symmetry operators associated with partial Lagrangians. The ideas of the procedure for a system of unperturbed partial differential equations are extended to a system of perturbed or approximate partial differential equations. These approximate Noether-type symmetry operators do not form a Lie algebra in general. The theory is applied to the perturbed linear and nonlinear (1 + 1) wave equations and the Maxwellian tails equation. We have also obtained new approximate conservation laws for these equations.