6 papers · 1 filter
Rohlin flows on the Cuntz algebra
Ola Bratteli, Akitaka Kishimoto, Derek W. Robinson
It is shown that certain quasi-free flows on the Cuntz algebra have the Rohlin property and therefore are cocycle-conjugate with each other. This, in particular, shows t…
Decidability of the isomorphism problem for stationary AF-algebras and the associated ordered simple dimension groups
Ola Bratteli, Palle E. T. Jorgensen, Ki Hang Kim +1
The notion of isomorphism of stable AF-C*-algebras is considered in this paper in the case when the corresponding Bratteli diagram is stationary, i.e., is associated with a single…
Representation Theory and Numerical AF-invariants: The representations and centralizers of certain states on O_d
Ola Bratteli, Palle E. T. Jorgensen, Vasyl Ostrovskyi
Let O_d be the Cuntz algebra on generators S_1,...,S_d, 2 \leq d < \infty, and let D_d \subset O_d be the abelian subalgebra generated by monomials S_αS_α^* =S_{α_{1}}...S_{α_{k}}S…
Homogeneity of the pure state space of the Cuntz algebra
Ola Bratteli, Akitaka Kishimoto
We prove that the automorphism group of a Cuntz algebra of finite order acts transitively on the set of pure states which are invariant under some gauge actions (which may depend o…
Trace acaling automorphisms of certain stable AF algebras II
Ola Bratteli, Akitaka Kishimoto
Two automorphisms of a simple stable AF algebra with a finite dimensional lattice of lower semicontinuous traces are shown to be outer conjugate if they act in the same way on the…
Non-stationarity of isomorphism between AF algebras defined by stationary Bratteli diagrams
Ola Bratteli, Palle E. T. Jorgensen, Ki Hang Kim +1
We first study situations where the stable AF-algebras defined by two square primitive nonsingular incidence matrices with nonnegative integer matrix elements are isomorphic even t…