Date of Award
1993
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Mathematics
First Advisor
Raymond Fabec
Abstract
It is shown that the C* algebra of a groupoid with Haar system has a natural split abelian extension. For a split abelian extension of a C* algebra it is shown that all representations of the original algebra extend to the split abelian extension. Under a reasonable assumption it is shown that states extend to a split abelian extension. Definitions for quasi-invariant and ergodic measures are given for split abelian extension of C* algebras, and it is shown when the split abelian extension is the natural extension of the C* algebra of a groupoid with Haar system that these definitions are equivalent to the groupoid definitions of quasi-invariant and ergodic. Irreducible representations that live over orbits on principal groupoids with Haar system are shown to be determined by the orbit. And in the case of an r-discrete, principal groupoid, it is shown how to reconstruct the Borel equivalence relation from the states of the natural extension of the C* algebra of the groupoid.
Recommended Citation
Curole, Mark Andrew, "Split Abelian Extensions of Calgebras." (1993). LSU Historical Dissertations and Theses. 5563.
https://repository.lsu.edu/gradschool_disstheses/5563
Pages
65
DOI
10.31390/gradschool_disstheses.5563