Helicity is the only integral invariant of volume-preserving transformations
نویسندگان
چکیده
منابع مشابه
Helicity is the only integral invariant of volume-preserving transformations.
We prove that any regular integral invariant of volume-preserving transformations is equivalent to the helicity. Specifically, given a functional I defined on exact divergence-free vector fields of class C(1) on a compact 3-manifold that is associated with a well-behaved integral kernel, we prove that I is invariant under arbitrary volume-preserving diffeomorphisms if and only if it is a functi...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 2016
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.1516213113