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Regular type of real hyper-surfaces in (almost) complex manifolds

J. -F. Barraud·E. Mazzilli
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Abstract

The regular type of a real hyper-surface M in an (almost) complex manifold at some point p is the maximal contact order at p of M with germs of non singular (pseudo) holomorphic disks. The main purpose of this paper is to give two intrinsic characterizations the type: one in terms of Lie brackets of a complex tangent vector field on M, the other in terms of some kind of derivatives of the Levi form.

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J. -F. Barraud, E. Mazzilli. 2003-04-11. Regular type of real hyper-surfaces in (almost) complex manifolds. https://arxiv.org/abs/math/0304146

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