Semibranching function systems and the representations of Cuntz-Krieger algebra associated to higher-rank graphs III
Sooran Kang
University of Otago
Date: Tuesday 13 October 2015
151012102710
Semibranching function systems and the representations of Cuntz-Krieger algebra associated to higher-rank graphs II
Sooran Kang
University of Otago
Date: Tuesday 6 October 2015
151012102605
Semibranching function systems and the representations of Cuntz-Krieger algebra associated to higher-rank graphs.
Sooran Kang
University of Otago
Date: Tuesday 29 September 2015
150928150631
REALISING THE TOEPLITZ ALGEBRA OF A HIGHER-RANK GRAPH AS A CUNTZ-KRIEGER ALGEBRA II
Yosafat Pangalela (Oscar)
University of Otago
Date: Tuesday 22 September 2015
150903145947
REALISING THE TOEPLITZ ALGEBRA OF A HIGHER-RANK GRAPH AS A CUNTZ-KRIEGER ALGEBRA I
Yosafat Pangalela (Oscar)
University of Otago
Date: Tuesday 15 September 2015
150903145823
Equilibrium states on C*-algebras associated to reducible 1-graphs.
Iain Raeburn
University of Otago
Date: Tuesday 8 September 2015
150903145226
Purely infinite groupoid C*-algebras
Jonathan Brown
University of Dayton, Ohio
Date: Tuesday 26 May 2015
Many C*-algebras, including graph and higher-rank graph algebras, have etale groupoid models. So the classification of etale groupoid C*-algebras has wide applicability. The seminal work of Kirchberg and Phillips showed that simple nuclear purely infinite C*-algebras (Kirchberg Algebras) satisfying the UCT can be classified by their ordered K-theory. It is thus interesting from a classification perspective to know which etale groupoids yield Kirchberg algebras and for this it is essential to understand precisely when an etale groupoid yields a purely infinite C*-algebra. In this talk we show that a simple etale groupoid C*-algebra is purely infinite if the nonzero positive elements of a canonical Cartan MASA are infinite. We further reduce these criteria in the case of higher rank graph groupoids. We also provide a general construction that shows we can use etale groupoids to provide concrete models for many Kirchberg algebras. We apply this construction to the groupoids associated to Bratteli diagrams and deduce that for every simple dimension group D not equal to Z, the stable Kirchberg algebra with K-theory (D, {0}) can be realised as the C * -algebra of an amenable principal groupoid.
150526100101
KMS states associated to finite directed graphs with a non-gauge action II
Richard McNamara
University of Otago
Date: Tuesday 5 May 2015
150428164327
KMS states associated to finite directed graphs with a non-gauge action I
Richard McNamara
University of Otago
Date: Tuesday 28 April 2015
150428164202
C*-algebras generated by semigroups of partial isometries
Ilija Tolich
University of Otago
Date: Tuesday 21 April 2015
150421100645
C*-algebras generated by semigroups of partial isometries
Ilija Tolich
University of Otago
Date: Tuesday 14 April 2015
150413125016
Equilibrium states on C*-algebras associated to local homeomorphisms II
Zahra Afsar
University of Otago
Date: Tuesday 31 March 2015
For a local homeomorphism, there is an associated Hilbert bimodule over a $C^*$-algebra. This Hilbert bimodule gives two main $C^*$-algebras: the Toeplitz algebra and its quotient the Cuntz-Pimsner algebra. Both algebras carry natural gauge actions of the circle, and hence one can obtain natural dynamics by lifting these actions to actions of the real line. In the literature, equilibrium states of Cuntz-Pimsner algebra are widely investigated. Recent works show that the Toeplitz algebra is expected to have many more equilibrium states. We focus on studying equilibrium states of the Toeplitz algebra. Then we reconcile our results in the Toeplitz algebra with those recent results of the Cuntz-Pimsner algebra. In this talk, after a brief explanation of basic definitions and notation, I will describe some of our main results.
150323145504
Equilibrium states on C*-algebras associated to local homeomorphisms
Zahra Afsar
University of Otago
Date: Wednesday 11 March 2015
For a local homeomorphism, there is an associated Hilbert bimodule over a $C^*$-algebra. This Hilbert bimodule gives two main $C^*$-algebras: the Toeplitz algebra and its quotient the Cuntz-Pimsner algebra. Both algebras carry natural gauge actions of the circle, and hence one can obtain natural dynamics by lifting these actions to actions of the real line. In the literature, equilibrium states of Cuntz-Pimsner algebra are widely investigated. Recent works show that the Toeplitz algebra is expected to have many more equilibrium states. We focus on studying equilibrium states of the Toeplitz algebra. Then we reconcile our results in the Toeplitz algebra with those recent results of the Cuntz-Pimsner algebra. In this talk, after a brief explanation of basic definitions and notation, I will describe some of our main results.
150304140847
Construction of a k-graph from a k-colored graph
Iain Raeburn
University of Otago
Date: Thursday 13 November 2014
141116140252
Visualization of k-graphs
Iain Raeburn
University of Otago
Date: Thursday 6 November 2014
141116140158
Categorical notion of k-graphs
Iain Raeburn
University of Otago
Date: Thursday 30 October 2014
141102123014
Quantum Heisenberg manifolds as twisted groupoid C*-algebras
Sooran Kang
University of Otago
Date: Thursday 23 October 2014
141023135510
The structure of quantum Heisenberg manifolds III
Sooran Kang
University of Otago
Date: Thursday 16 October 2014
141016135248
The structure of quantum Heisenberg manifolds II
Sooran Kang
University of Otago
Date: Thursday 2 October 2014
141002143545
The structure of quantum Heisenberg manifolds I
Sooran Kang
University of Otago
Date: Thursday 25 September 2014
141002143403
Picard group and symmetric Hilbert C*-bimodules
Sooran Kang
University of Otago
Date: Thursday 18 September 2014
140921160933
Realization of crossed products by Hilbert C*-bimodules as Cuntz-Pimsner algebras II
Sooran Kang
University of Otago
Date: Thursday 11 September 2014
140910145348
Realization of crossed products by Hilbert C*-bimodules as Cuntz-Pimsner algebras I
Sooran Kang
University of Otago
Date: Thursday 4 September 2014
140910145215
Quasi-lattice ordered groups and their C*-algebras II
Ilija Tolich
University of Otago
Date: Thursday 24 July 2014
140723162558
Quasi-lattice ordered groups and their C*-algebras I
Ilija Tolich
University of Otago
Date: Thursday 17 July 2014
140717140332
Spatial realization of KMS_beta states on C*-algebras associated to a finite k-graph
Sooran Kang
Date: Thursday 26 September 2013
130925164549
KMS states for generalised gauge actions II
Richard McNamara
Date: Thursday 19 September 2013
130925164729
KMS states for generalised gauge actions
Richard McNamara
Date: Thursday 12 September 2013
130911145822
KMS states of Toeplitz algebras II
Zahra Afsar
Date: Thursday 5 September 2013
130904140832
KMS states of Toeplitz algebras
Zahra Afsar
Date: Thursday 22 August 2013
130820154844
Power partial isometries III
Ilija Tolich
Date: Thursday 15 August 2013
130808144146
Power partial isometries II
Ilija Tolich
Date: Thursday 8 August 2013
130808104238
Power partial isometries
Ilija Tolich
Date: Thursday 1 August 2013
130808105053
Purely infinite simple groupoid algebras II
Lisa Orloff Clark
Date: Thursday 25 July 2013
130808105215
Purely infinite simple groupoid algebras
Lisa Orloff Clark
Date: Thursday 18 July 2013
130808144510
Quasidiagonal C*-algebras II
Astrid an Huef
Date: Friday 5 July 2013
130808144824
Quasidiagonal C*-algebras
Astrid an Huef
Date: Thursday 27 June 2013
130808144947
Fell Bundles and Gradings IV
Iain Raeburn
Date: Friday 17 May 2013
130808145305
Fell Bundles and Gradings III
Iain Raeburn
Date: Friday 10 May 2013
130808145757
Fell Bundles and Gradings II
Iain Raeburn
Date: Friday 3 May 2013
130808145824
Fell Bundles and Gradings
Iain Raeburn
Date: Friday 26 April 2013
130808145947
Textile system and its applications II
Sooran Kang
Date: Friday 12 April 2013
130808144406
Textile system and its applications
Sooran Kang
Date: Thursday 4 April 2013
130808144225
New C*-completions of discrete groups IV
Astrid an Huef
Date: Friday 22 March 2013
130808150839
New C*-completions of discrete groups III
Astrid an Huef
Date: Friday 15 March 2013
130808150813
New C*-completions of discrete groups II
Astrid an Huef
Date: Friday 8 March 2013
130808150537
New C*-completions of discrete groups
Astrid an Huef
Date: Friday 1 March 2013
130808150030
Simplicity of groupoid C*-algebras
Jon Brown
University of Otago
Date: Thursday 12 July 2012
120711105914
Gelfand-Kirillov dimension of Leavitt path algebras
John Clark
University of Otago
Date: Thursday 5 July 2012
120702122013
Groupoids and Baire Category Theorem
Lisa Orloff Clark
University of Otago
Date: Friday 29 June 2012
120627165240