Re: Chu(Ab,circle) is abelian

And to anticipate Vaughan's question, no chu(Ab,circle) is not abelian, roughly for the same reasons as topological ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ and localic abelian groups.

Actually I was going to ask about Ab. I thought it was abelian groups but (maybe I'm just the last to be told) the context suggests Ab = topological abelian groups. Is there life in discrete circles? (To reconcile the subject line with the underlined line you need to know Mike's usage: the large print giveth and the small print taketh away. Chu is to chu as preordered sets are to posets, or topological spaces to T_0 spaces.) Vaughan