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Discrete and Backlund (!) transformations of SDYM system

A. N. Leznov
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Abstract

Symmetry of SDYM equations for "physically restricted solution" with hermitian group element $G=G^H$ in representation of Yang is described. Such transformation $D^B$ pass some PRS to the new one of the same kind. Transformation contain $2N_G$ arbirtrary functions of two independent arguments, where $N_G$ dimension of the gauge semi-simple algebra. These functions may be considered as additional parameters typical for Backlund aproach and by this reason we use term Backlund for this transformation.

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A. N. Leznov. 2005-04-01. Discrete and Backlund (!) transformations of SDYM system. https://arxiv.org/abs/math-ph/0504004

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