Illinois Journal of Mathematics

Remarks on HNN extensions in operator algebras

Yoshimichi Ueda

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It is shown that any HNN extension is precisely a compression by a projection of a certain amalgamated free product in the framework of operator algebras. As its applications several questions for von Neumann algebras or C*-algebras arising as HNN extensions are considered.

Article information

Illinois J. Math., Volume 52, Number 3 (2008), 705-725.

First available in Project Euclid: 28 September 2009

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 46L09: Free products of $C^*$-algebras 46L10: General theory of von Neumann algebras
Secondary: 46L54: Free probability and free operator algebras


Ueda, Yoshimichi. Remarks on HNN extensions in operator algebras. Illinois J. Math. 52 (2008), no. 3, 705--725. doi:10.1215/ijm/1254143997.

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