Conserved Forms derived from Symmetries

  1. Muriel, C. 1
  2. Romero, J.L. 1
  1. 1 Department of Mathematics. University of Cádiz. 11510 Puerto Real. Cádiz. Spain
Actas:
79th Annual Meeting of the International Association of Applied Mathematics and Mechanics (GAMM), Bremen 2008

ISSN: 1617-7061

Año de publicación: 2008

Volumen: 8

Número: 1

Páginas: 10747-10748

Tipo: Aportación congreso

DOI: 10.1002/PAMM.200810747 GOOGLE SCHOLAR lock_openAcceso abierto editor

Resumen

For first order scalar ordinary differential equations, a well–known result of Sophus Lie states that a Lie point symmetry can be used to construct an integrating factor and conversely.However, there exist higher order equations without Lie point symmetries that admit integrating factors or that are exact. We present a method based on λ-symmetries to calculate integrating factors. An example of a second order equation without Lie point symmetries illustrates how the method works in practice and how the computations that appear in other methods may be simplified. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

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