| 概要 | This talk is based on a joint work with M.Ikeda and
S.Katayama. We consider the initial value problem for a
three-component system of quadratic derivative nonlinear
Schrodinger equations in two space dimensions with the
masses satisfying a resonance relation. We introduce a
structural condition on the nonlinearity under which the
solution is asymptotically free in the large time. Several
related problems will be also discussed. |