Gevrey hypoellipticity for a class of partial differential equations with high multiplicity (Q2704044)

This paper deals with Gevrey hypoellipticity for a class of partial differential equations having characteristics of higher multiplicity. As no Levi-type conditions are imposed, the main hypoelliptic properties depend on the lower-order terms in a rather complicated way. The proofs here proposed are based on the Hörmander's \(S^m_{\rho,\delta}\) techniques which are microlocalized in an appropriate way in the Gevrey spaces. That paper is an extension of some previous investigations of the author jointly with L. Rodino and A. Oliaro.NEWLINENEWLINEFor the entire collection see [Zbl 0958.00030].