Resumen de About Gevrey Hypoellipticity of pseudodifferential operators associated to the class of Hörmander symbols of Gevrey type
Mohammed Hazi
Treves, F., [15], proved the hypoellipticity of some regular operators. Later, Hörmander, L.,[11] Durand, M., [7], and Oleinik, O.A. & Radkevic, E. V., [13], considered independently second order operators which are sum of squares of real vector fields; they gave criteria of hypoellipticity. Derridj, M. & Zuily, C., [5], studied their Gevrey regularity. Moreover, Baouendi, M. S.& Goulaouic, C., [1] and then Derridj, M. & Zuily, C., [6], obtained some results of analyticity and Gevrey regularity for some degenerate elliptic operators. Here, we aim to prove Gevrey hypoellipticity of pseudodifferential operators associated to Hörmander symbols of Gevrey type.
