## Illinois Journal of Mathematics

### Constructions of exotic group $C$∗-algebras

Matthew Wiersma

#### Abstract

Let $\Gamma$ be a discrete group. When $\Gamma$ is nonamenable, the reduced and full group $C$∗-algebras differ and it is generally believed that there should be many intermediate $C$∗-algebras, however few examples are known. In this paper, we give new constructions and compare existing constructions of intermediate group $C$∗-algebras for both generic and specific groups $\Gamma$.

#### Article information

Source
Illinois J. Math., Volume 60, Number 3-4 (2016), 655-667.

Dates
Revised: 19 April 2017
First available in Project Euclid: 22 September 2017

https://projecteuclid.org/euclid.ijm/1506067285

Digital Object Identifier
doi:10.1215/ijm/1506067285

Mathematical Reviews number (MathSciNet)
MR3705441

Zentralblatt MATH identifier
1373.22014

#### Citation

Wiersma, Matthew. Constructions of exotic group $C$∗-algebras. Illinois J. Math. 60 (2016), no. 3-4, 655--667. doi:10.1215/ijm/1506067285. https://projecteuclid.org/euclid.ijm/1506067285

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