Bounded countable atomic compactness of ordered groups
Extensions of dimension groups and AF C*-algebras.
Induced subsystems associated to a Cantor minimal system
Let (X,T) be a Cantor minimal system and let (R,) be the associated étale equivalence relation (the orbit equivalence relation). We show that for an arbitrary Cantor minimal system (Y,S) there exists a closed subset Z of X such that (Y,S) is conjugate to the subsystem (Z,T̃), where T̃ is the induced map on Z from T. We explore when we may choose Z to be a T-regular and/or a T-thin set, and we relate T-regularity of a set to R-étaleness. The latter concept plays an important role in the study of...
Matrices of positive polynomials.
Presentations of subshifts and their topological conjugacy invariants.
Stability of -algebras is not a stable property.
Trace maps in algebraic K-theory and the Coates-Wiles homomorphism.