1997/03/30 by A. Zabrodin · 2 citations
Physics and Astronomy · #solv-int #hep-th #nlin.SI
paper · pdf · doi:10.1007/bf02634165
LaTeX, 43 pages, LaTeX figures (with emlines2.sty)
arxiv created 1997/03/30 · arxiv updated 2016/09/08
A review of selected topics in Hirota's bilinear difference equation (HBDE) is given. This famous 3-dimensional difference equation is known to provide a canonical integrable discretization for most important types of soliton equations. Similarly to the continuous theory, HBDE is a member of an infinite hierarchy. The central point of our exposition is a discrete version of the zero curvature condition explicitly written in the form of discrete Zakharov-Shabat equations for M-operators realized as difference or pseudo-difference operators. A unified approach to various types of M-operators and zero curvature representations is suggested. Different reductions of HBDE to 2-dimensional equations are considered. Among them discrete counterparts of the KdV, sine-Gordon, Toda chain, relativistic Toda chain and other typical examples are discussed in detail.