Skip to main content

Timeline for K-Theory of $C^{*}(X)$

Current License: CC BY-SA 4.0

9 events
when toggle format what by license comment
Aug 30, 2020 at 20:28 vote accept Peg Leg Jonathan
Aug 29, 2020 at 20:19 comment added Peg Leg Jonathan I appreciate it, sir.
Aug 29, 2020 at 19:11 comment added Ulrich Pennig Karen Strung has good notes about C*-algebras in the context of the classification programme. They also treat K-theory and can be found here: strung.me/karen/CStarIntroDraft.pdf . Maybe these are useful.
Aug 29, 2020 at 18:54 comment added Peg Leg Jonathan @UlrichPennig Thank you very much sir. I learned a lot from your answer. It is clear now for me.
Aug 29, 2020 at 18:49 comment added Ulrich Pennig As for the group $C^*$-algebra, I guess the answer is: It is what it is. You can view it as the direct limit over all $C^*$-algebras $C^*(S_n)$, which reveals it as an AF-algebra, if that helps. The algebras $C^*(S_n)$ are of course finite-dimensional and can be seen as direct sums of matrix algebras.
Aug 29, 2020 at 18:47 comment added Ulrich Pennig You wrote you consider the group of finite support bijections of $\mathbb{N}$. Such a bijection is the identity outside of a finite set and permutes the elements in that finite set. Therefore you can identify the group of finite support bijections with the union over all groups $S_n$. Does that help?
Aug 29, 2020 at 18:04 comment added Nik Weaver @PegLegScott please don't take this the wrong way, but it really doesn't look like you have enough background to be studying K-theory of C*-algebras. Why not start a little further back?
Aug 29, 2020 at 16:46 comment added Peg Leg Jonathan Thank you for your answer sir, but I don't understand the first paragraph: The group is infinite symmetric group, how do you know that? And second what is its $C^{*}$-algebra? Sorry if my questions are so dumb.
Aug 29, 2020 at 16:14 history answered Ulrich Pennig CC BY-SA 4.0