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arXiv · 2107.12451

Sums of squares III: hypoellipticity in the infinitely degenerate regime

Lyudmila Korobenko·Eric T. Sawyer
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Abstract

This is the third in a series of papers dealing with sums of squares and hypoellipticity in the infinitely degenerate regime. We establish a C^2,delta generalization of M. Christ's sum of squares theorem, and use a bootstrap argument with the sum of squares theorem for matrix functions in the second paper of this series, in order to prove a hypoellipticity theorem generalizing work in the infinitely degenerate regime to include nondiagonal operators and more general degeneracies.

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Lyudmila Korobenko, Eric T. Sawyer. 2021-07-26. Sums of squares III: hypoellipticity in the infinitely degenerate regime. https://arxiv.org/abs/2107.12451

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