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An integrable discretization of KdV at large times

M Boiti·F Pempinelli·B Prinari·A. Spire
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Abstract

An "exact discretization" of the Schroedinger operator is considered and its direct and inverse scattering problems are solved. It is shown that a differential-difference nonlinear evolution equation depending on two arbitrary constants can be solved by using this spectral transform and that for a special choice of the constants it can be considered an integrable discretization of the KdV equation at large times. An integrable difference-difference equation is also obtained.

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M Boiti, F Pempinelli, B Prinari, A. Spire. 2001-01-13. An integrable discretization of KdV at large times. https://doi.org/10.1088/0266-5611%2F17%2F3%2F310

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