Skip to main content
8 events
when toggle format what by license comment
Feb 6, 2020 at 19:23 comment added Caleb Eckhardt It appears that the answer to your first question is unknown. In the (recent) second edition of Pedersen's "C*-algebras and their automorphism groups" the editors write that your question 1 "remains mysterious." This is in Section 6.8.9. They expand on their statement in the following section 6.9.
Feb 5, 2020 at 23:09 comment added Bedovlat YCor, 2 irreducibles? Where from? If there is exactly 1 primitive ideal then the injectivity implies that there is 1 equivalence class of irreducibles.
Feb 5, 2020 at 22:56 comment added YCor The converse of what? the main statement is not written as an implication. You mean that for a C$^*$-algebra, postliminal implies the given injectivity property? Also, a simple C$^*$-algebra with the given injectivity property means a C$^*$-algebra with only 1 or 2 irreducible representations up to equivalence, if I'm correct...?
Feb 5, 2020 at 22:52 history edited YCor
edited tags
Feb 5, 2020 at 22:30 comment added Bedovlat Yes, I can't find a simplicity argument in that paper.
Feb 5, 2020 at 21:44 comment added Yemon Choi (This is merely a comment rather than an answer since I expect Nik Weaver can turn up to give a better answer :) )
Feb 5, 2020 at 21:43 comment added Yemon Choi Under additional set-theoretic assumptions, Akemann and Weaver demonstrated the existence of a unital Cstar algebra that has only one irrep up to unitary equivalence; it seems to me that such a beast must be simple, and it can't be separable or Type I by classical results
Feb 5, 2020 at 21:01 history asked Bedovlat CC BY-SA 4.0