A counterexample to $C^k$-regularity for the Newlander-Nirenberg theorem
نویسندگان
چکیده
We give an example of $C^k$-integrable almost complex structure that does not admit a corresponding $C^{k+1}$-complex coordinate system.
منابع مشابه
The Newlander-nirenberg Theorem
For any kind of geometry on smooth manifolds (Riemannian, Complex, foliation, ...) it is of fundamental importance to be able to determine when two objects are isomorphic. The method of equivalence using G-structures is a systematic way to classify the local invariants of a particular geometry. For example, these ideas can be used to show that the only local invariants of a Riemannian manifold ...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 2021
ISSN: ['2330-1511']
DOI: https://doi.org/10.1090/proc/15270