The Godbillon measure of amenable foliations
نویسندگان
چکیده
منابع مشابه
Godbillon-vey Invariants for Families of Foliations
The classical Godbillon-Vey invariant is an odd degree cohomology class that is a cobordism invariant of a single foliation. Here we investigate cohomology classes of even degree that are cobordism invariants of (germs of) 1-parameter families of foliations. In this paper we study an analogue of the classical Godbillon-Vey invariant [6] that is an invariant not of a single foliation but of a fa...
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Let $K$ be a locally compact hypergroup with left Haar measure and let $L^1(K)$ be the complex Lebesgue space associated with it. Let $L^infty(K)$ be the dual of $L^1(K)$. The purpose of this paper is to present some necessary and sufficient conditions for $L^infty(K)^*$ to have a topologically left invariant mean. Some characterizations of amenable hypergroups are given.
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ژورنال
عنوان ژورنال: Journal of Differential Geometry
سال: 1986
ISSN: 0022-040X
DOI: 10.4310/jdg/1214440118