Hokkaido University Preprint Series in Mathematics
Consider the nonlinear wave equation with zero mass in two space dimensions. hen it comes to the associated Cauchy problem with small initial data, the known existence esults are already sharp; those require the data to decay at a rate k ¸ kc, where kc is a critical ecay rate that depends on the order of the nonlinearity. However, the known scattering results reat only the supercritical case k > kc. In this paper, we prove the existence of the scattering perator for the full optimal range k ¸ kc.