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Embedding Theorems in Group C*-Algebras

Published online by Cambridge University Press:  20 November 2018

Tan-Yu Lee*
Affiliation:
Department of Mathematics, University of AlabamaUniversity, AL 35486
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Abstract

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Let G be a locally compact group and H an open subgroup of G. The embeddings of group C*-algebras associated with H into the group C*-algebras associated with G are studied. Three conditions for the embeddings given in terms of C*-norms of the group algebras, group representations and positive definite functions are shown to be equivalent. As corollary, we prove that the full C*-algebra of H can be embedded into the full C*-algebra of G in a natural way as well as the case for the reduced group C*-algebras. We also show that the embeddings hold for their duals and double duals.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1983

Footnotes

This paper is essentially a generalization of some results in the author's Ph.D. thesis, written at the University of California, Santa Barbara, under the direction of Professor Charles A. Akemann.

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