2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/230568The two-dimensional Zakharov system is shown to have a unique global solution for data without finite energy if the L^2 - norm of the Schrödinger part is small enough. The proof uses a refined I-method originally initiated by Colliander, Keel, Staffilani, Takaoka and Tao. A polynomial growth bound for the solution is also given.17 pages, updated references, final version to appear in Analysis 29, 1001-1017 (2009)Analysis of PDEs35Q55; 35L70text