Characterization of amenable semigroups with a unique invariant mean
نویسندگان
چکیده
منابع مشابه
A CHARACTERIZATION OF EXTREMELY AMENABLE SEMIGROUPS
Let S be a discrete semigroup, m (S) the space of all bounded real functions on S with the usualsupremum norm. Let Acm (S) be a uniformly closed left invariant subalgebra of m (S) with 1 c A. We say that A is extremely left amenable if there isamultiplicative left invariant meanon A. Let P = {h ?A: h =|g-1,g | forsome g ?A, s ?S}. It isshown that . A is extremely left amenable if and only ...
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ژورنال
عنوان ژورنال: Proceedings of the Japan Academy, Series A, Mathematical Sciences
سال: 1983
ISSN: 0386-2194
DOI: 10.3792/pjaa.59.321