Extending multipliers from semigroups

Authors:
Marcelo Laca and Iain Raeburn

Journal:
Proc. Amer. Math. Soc. **123** (1995), 355-362

MSC:
Primary 20M30; Secondary 47A20, 47D03

MathSciNet review:
1227519

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Abstract: A multiplier on a normal subsemigroup of a group can be extended to a multiplier on the group. This is used to show that normal cancellative semigroups have the same second cohomology as the group they generate, generalising earlier results of Arveson, Chernoff, and Dinh. The main tool is a dilation theorem for isometric multiplier representations of semigroups.

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Additional Information

DOI:
http://dx.doi.org/10.1090/S0002-9939-1995-1227519-6

Keywords:
Semigroup multiplier,
isometric multiplier representations,
second cohomology

Article copyright:
© Copyright 1995
American Mathematical Society