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Global analytic, Gevrey and C∞ hypoellipticity on the 3-torus

✍ Scribed by A. Alexandrou Himonas; Gerson Petronilho; L. A. Carvalho dos Santos


Publisher
John Wiley and Sons
Year
2011
Tongue
English
Weight
223 KB
Volume
285
Category
Article
ISSN
0025-584X

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✦ Synopsis


Abstract

It is proved that a class of sub‐Laplacians on the 3‐dimensional torus is globally analytic, Gevrey and C^∞^ hypoelliptic if and only if either a Diophantine condition holds or there is a point of finite type for the vector fields defining the operator under consideration. This work is motivated by the desire of attaining a better understanding of necessary and sufficient conditions for the global Gevrey and C^∞^ hypoellipticity of a sub‐Laplacian on a compact analytic manifold. This together with the more delicate local hypoellipticity are well‐known open problems in the theory of linear partial differential equations.