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arXiv · 0802.3581

Reduction of systems of first-order differential equations via Lambda-symmetries

G. Cicogna
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Abstract

The notion of lambda-symmetries, originally introduced by C. Muriel and J.L. Romero, is extended to the case of systems of first-order ODE's (and of dynamical systems in particular). It is shown that the existence of a symmetry of this type produces a reduction of the differential equations, restricting the presence of the variables involved in the problem. The results are compared with the case of standard (i.e. exact) Lie-point symmetries and are also illustrated by some examples.

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G. Cicogna. 2008-02-25. Reduction of systems of first-order differential equations via Lambda-symmetries. https://doi.org/10.1016/j.physleta.2008.02.041

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