INTEGRABILITY AND SEIBERG-WITTEN EXACT SOLUTION

The exact Seiberg-Witten (SW) description of the light sector in the N = 2 SUSY 4d Yang-Mills theory [N. Seiberg and E. Witten, Nucl. Phys. B 430 (1994) 485 (E); B 446 (1994) 19] is reformulated in terms of int egrable systems and appears to be a Gurevich-Pitaevsky (GP) [A. Gurevi ch and L. Pitaevsky, JETP 65 (1973) 65; see also, S. Novikov, S. Manak ov, L. Pitaevsky and V. Zakharov, Theory of solitons] solution to the elliptic Whitham equations, We consider this as an implication that th e dynamical mechanism behind the SW solution is related to integrable systems on the moduli space of instantons. We emphasize the role of th e Whitham theory as a possible substitute of the renormalization-group approach to the construction of low-energy effective actions.