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On the notion of conditional symmetry of differential equations

G. Cicogna·M. Laino
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Abstract

Symmetry properties of PDE's are considered within a systematic and unifying scheme: particular attention is devoted to the notion of conditional symmetry, leading to the distinction and a precise characterization of the notions of ``true'' and ``weak'' conditional symmetry. Their relationship with exact and partial symmetries is also discussed. An extensive use of ``symmetry-adapted'' variables is made; several clarifying examples, including the case of Boussinesq equation, are also provided.

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G. Cicogna, M. Laino. 2006-03-09. On the notion of conditional symmetry of differential equations. https://doi.org/10.1142/s0129055x06002553

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