Yuriy BERKELA
Ivan Franko National University of Lviv,
1 Universytetska Street, Lviv, 79000, UKRAINE
E-mail: yuri@rakhiv.ukrtel.net

Integration of the bihamiltonian systems by dressing method

Abstract: We consider of nonlinear bi-hamiltonian systems of evolution equations in the form
ut = K[u],
(1)
where u = (u1,...,um)(x,t) be a smooth vector-function, and K[u] be a linear functional.

Moving from, so-called, "recursion" Lax representation for system (1), known at present time for most integrable systems in dimension (1+1) [1]
Lt = [K¢,L],
(2)
where L be a generating (symmetrical-recursion) operator, K¢ = K¢[u] be a Freshe derivative of functional K[u] (1), we propose the method of integration of system (1), which is basing on idea of dressing transformations of Zakharov-Shabat and Dorboux-Matveev.

Factorization of generating operator L with two hamiltonian operators L ³ M: L = ML-1 admits to describe whole group of reductions associating linear integro-differential system
L j = lj

jt = K¢[u]j,
where l be a spectral parameter.

Wide classes of exact solutions of system (1) may be obtain as nonlinear superposition of linear waves, analogically to method of integration of nonlinear models with integro-differential Lax-Zakharov-Shabat representations [2-4].

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