# Mathematics Colloquium

#### Thursday, January 18, 1996, 4:00pm

#### 102 Bradley Hall

## Professor Neal Fowler

#### University of Newcastle, Australia

speaks on
### States of Toeplitz-Cuntz algebras

**Abstract.** Motivated by work of W. Arveson on the spectral
C*-algebra of an E_0-semigroup, we discuss how locally normal weights on a certain irreducible operator algebra can be used to
study states of Toeplitz-Cuntz algebras. As an application, we classify
those states of the Cuntz algebra O_{\infty} whose restriction to the
fixed point algebra under the action of the gauge group is a pure
product state.
**Tea. ** High tea will be served at 3:30pm in the Lounge.

**Emmy's. ** Certain refreshments will be available at the Emmy's after the talk.

**Host. ** Dana Williams will be the host, anybody interested in having dinner with the speaker should contact Dana (Ext. 6-2990).