B. Enriquez et Bl. Feigin, INTEGRALS OF MOTION OF THE CLASSICAL LATTICE SINE-GORDON SYSTEM, Theoretical and mathematical physics, 103(3), 1995, pp. 738-756
We compute the local integrals of motions of the classical limit of th
e lattice sine-Gordon system, using a geometrical interpretation of th
e local sine-Gordon variables. Using an analogous description of the s
creened local variables, we show that these integrals are in involutio
n. We present some remarks on relations with the situation at the root
s of 1 and results on another latticization (linked to the principal s
ubalgebra of <(sl)over cap>(2) rather than the homogeneous one). Final
ly, we analyze a module of ''screened semilocal variables,'' on which
the whole <(sl)over cap>(2) acts.