Annals of Functional Analysis

Commuting contractive idempotents in measure algebras

Nico Spronk

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We determine when contractive idempotents in the measure algebra of a locally compact group commute. We consider a dynamical version of the same result. We also look at some properties of groups of measures whose identity is a contractive idempotent.

Article information

Ann. Funct. Anal., Volume 7, Number 1 (2016), 136-149.

Received: 15 March 2015
Accepted: 11 August 2015
First available in Project Euclid: 22 December 2015

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Digital Object Identifier

Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 43A05: Measures on groups and semigroups, etc.
Secondary: 43A77: Analysis on general compact groups 43A40: Character groups and dual objects

measure algebra idempotent groups of measures


Spronk, Nico. Commuting contractive idempotents in measure algebras. Ann. Funct. Anal. 7 (2016), no. 1, 136--149. doi:10.1215/20088752-3428247.

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