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 note a relation between mu-symmetries and conditional invariants. We also consider the case where the variational principle is itself formulated as requiring vanishing variation under mu-prolonged variation fields, leading to modified Euler-Lagrange equations. In this setting, mu-symmetries of the Lagrangian correspond to standard conservation laws as in the standard Noether theorem. We finally propose some applications and examples.
Autori interni: | |
Autori: | Cicogna G; Gaeta G |
Titolo: | Noether theorem for mu-symmetries |
Anno del prodotto: | 2007 |
Digital Object Identifier (DOI): | 10.1088/1751-8113/40/39/013 |
Appare nelle tipologie: | 1.1 Articolo in rivista |