Positive definite bounded matrices and a characterization of amenable groups
نویسندگان
چکیده
منابع مشابه
Extensions of Positive Definite Functions on Amenable Groups
Let S be a subset of a amenable group G such that e ∈ S and S = S. The main result of the paper states that if the Cayley graph of G with respect to S has a certain combinatorial property, then every positive definite operator-valued function on S can be extended to a positive definite function on G. Several known extension results are obtained as a corollary. New applications are also presented.
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 1985
ISSN: 0002-9939
DOI: 10.1090/s0002-9939-1985-0806070-2