On the Treves theorem for the AKNS equation

Carlo Morosi; Livio Pizzocchero

doi:10.1063/1.1805730

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On the Treves theorem for the AKNS equation

Carlo Morosi·Livio Pizzocchero

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Abstract

According to a theorem of Treves, the conserved functionals of the AKNS equation vanish on all pairs of formal Laurent series of a specified form, both of them with a pole of the first order. We propose a new and very simple proof for this statement, based on the theory of Bäcklund transformations; using the same method, we prove that the AKNS conserved functionals vanish on other pairs of Laurent series. The spirit is the same of our previous paper on the Treves theorem for the KdV, with some non trivial technical differences.

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Carlo Morosi, Livio Pizzocchero. 2004-07-09. On the Treves theorem for the AKNS equation. https://doi.org/10.1063/1.1805730

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