Guido Gentile, Vieri Mastropietro
Tree expansion and multiscale analysis for KAM tori
(92K, Plain Tex)

ABSTRACT.  We prove that the perturbative expansion for
the KAM invariant tori of the Thirring model (with interaction
depending also on the action variables) is convergent by using
techniques usual in quantum field theory like the multiscale
decomposition and the tree expansion. The proof follows the
ideas of Eliasson, and extends the results found
in the case of an action-independent interaction potential.