A remark on sums of squares of complex vector fields

2005/03/23 by Michael Christ, Christ, Michael
Mathematics · #Advanced Differential Equations and Dynamical Systems #Advanced Topics in Algebra #Holomorphic and Operator Theory #math.AP #math.CV #msc:32W10 #msc:35H10

paper · pdf · doi:10.48550/arxiv.math/0503506

5 pages

arxiv created 2005/03/23 · arxiv updated 2009/12/01

Abstract

This note is a comment on a recent paper by J. J. Kohn. We give an example of a second order partial differential operator, expressed as a sum of squares of complex vector fields satisfying the bracket condition, that is not hypoelliptic.

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