321 reputation
17
bio website maths.swan.ac.uk/staff/ejb
location Swansea, Wales
age
visits member for 1 year, 9 months
seen Aug 11 at 14:20

Jul
24
awarded  Tumbleweed
Jul
17
asked the push forward of the differential idea of sheaf
Jul
4
awarded  Yearling
Jul
4
asked allowing `discontinuous functions' into a C* algebra
Jul
2
awarded  Curious
Jun
26
comment complementary bundle for a divisor
More thought - the direct sum by preference, if not then any related construction would be welcome.
Jun
26
comment complementary bundle for a divisor
Honestly, I do not know which. Whichever works nicely I guess. I had thought of the first, but anything nice to say about the second would be welcome. Modules with connection in noncommutative geometry form an abelian category, so either approach could be used in noncommutative geometry.
Jun
26
asked complementary bundle for a divisor
Jun
10
comment When is the corner algebra $PM_n(A)P$ isomorphic to $A$?
Just got a copy of Brown's paper - I will read it!
Jun
10
comment When is the corner algebra $PM_n(A)P$ isomorphic to $A$?
That is a good point - hopefully there are other cases - there are classically line bundles not with the same K-theory class as the trivial bundle. (E.g. on the sphere.)
Jun
9
asked When is the corner algebra $PM_n(A)P$ isomorphic to $A$?
Jun
4
comment Universal unital $C^*$ algebra generated by the relations of an n by n projection
Thanks, that is just what I was looking for. Blackadar in turn refers to a paper by L. Brown "Ext of certain free product C* algebras", J. Operator Theory 6. I have some reading to do.
Jun
4
accepted Universal unital $C^*$ algebra generated by the relations of an n by n projection
Jun
4
revised Universal unital $C^*$ algebra generated by the relations of an n by n projection
added 267 characters in body
Jun
4
comment Universal unital $C^*$ algebra generated by the relations of an n by n projection
That is interesting - also in the case where the diagonals sum to $1+\lambda$ you get the noncommutative fuzzy sphere with parameter $\lambda$. I am not sure who first pointed that out. I shall do a bit more of an edit above to explain why these algebras are so interesting in the general case.
Jun
4
asked Universal unital $C^*$ algebra generated by the relations of an n by n projection
May
21
comment positive maps and bimodules
Thanks! I was hoping that there was a result somewhere, and that looks just what I wanted. It would be very good to have a journal or book reference for it.
May
21
accepted positive maps and bimodules
May
21
awarded  Commentator
May
21
comment positive maps and bimodules
I don't necessarily expect composition to be compatible - just about any bimodule would be interesting.