1998/10/01 by A. Zabrodin, Zabrodin, A.
Physics and Astronomy · #Exactly Solvable and Integrable Systems (nlin.SI) #FOS: Physical sciences #High Energy Physics - Theory (hep-th) #hep-th #nlin.SI #solv-int
paper · pdf · doi:10.48550/arxiv.solv-int/9810003
14 pages, latex
arxiv created 1998/10/01 · arxiv updated 2009/11/30
We prove that the tau-function of the integrable discrete sine-Gordon model apart from the "standard" bilinar identities obeys a number of "non-standard" ones. They can be combined into a bivector 3-dimensional difference equation which is shown to contain Hirota's difference analogue of the sine-Gordon equation and both auxiliary linear problems for it. We observe that this equation is most naturally written in terms of the quantum R-matrix for the XXZ spin chain and looks then like a relation of the "vertex-face correspondence" type.