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arXiv · 0705.1663

Discrete nonlinear hyperbolic equations. Classification of integrable cases

Vsevolod E. Adler·Alexander I. Bobenko·Yuri B. Suris
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Abstract

We consider discrete nonlinear hyperbolic equations on quad-graphs, in particular on the square lattice. The fields are associated to the vertices and an equation Q(x_1,x_2,x_3,x_4)=0 relates four fields at one quad. Integrability of equations is understood as 3D-consistency. The latter is a possibility to consistently impose equations of the same type on all the faces of a three-dimensional cube. This allows to set these equations also on multidimensional lattices Z^N. We classify integrable equations with complex fields x, and Q affine-linear with respect to all arguments. The method is based on analysis of singular solutions.

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Vsevolod E. Adler, Alexander I. Bobenko, Yuri B. Suris. 2007-05-11. Discrete nonlinear hyperbolic equations. Classification of integrable cases. https://arxiv.org/abs/0705.1663

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