FACTORIZATION OF LOOP ALGEBRAS OVER so(4) AND INTEGRABLE NONLINEAR DIFFERENTIAL EQUATIONS

摘要

We consider factoring subalgebras for loop algebras over so(4). Given a factoring subalgebra, we find (in terms of coefficients of commutator relations) an explicit form of (1) the corresponding system of the chiral-field-equation type, (2) the corresponding two-spin model of the Landau-Lifshitz equation, and (3) the corresponding Hamiltonian system of ordinary differential equations with homogeneous quadratic Hamiltonian and linear so(4)-Poisson brackets.