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Apr 13, 2017 at 12:19 history edited CommunityBot
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Feb 15, 2016 at 13:59 vote accept Ali Taghavi
Feb 14, 2016 at 6:42 answer added David Handelman timeline score: 5
Jan 30, 2016 at 10:40 comment added Ali Taghavi @EricWofsey thanks for your comment. do you think that the space of strictly upper triangle matrices gives finite non trivial k_ group?
Jan 30, 2016 at 10:17 comment added Eric Wofsey If you allow non-unital algebras, it is easy to find a finite-dimensional algebra $A$ such that $K_0(A)$ is trivial (for instance, let $A=\mathbb{C}$ with the zero multiplication; then over $\tilde{A}=\mathbb{C}[x]/(x^2)$ all projective modules are free). Whether $K_0(A)$ can be finite but nontrivial seems a lot harder.
Jan 30, 2016 at 9:31 comment added Ali Taghavi @AlainValette Prof Valette, What is $K_{0}(A)$ where $A=$ is the space of strictly upper triangle matrices ?
Jan 29, 2016 at 21:55 comment added Alain Valette @Fermando: Because, for non-unital algebras $K_0(A)$ is defined as $\ker[K_0(\tilde{A})\rightarrow K_0(k)=\mathbb{Z}]$, where $\tilde{A}$ is the unitization of $A$, so you don't deal with f.g. projective modules, but with differences of modules having the same dimension.
Jan 29, 2016 at 16:27 comment added Fernando Muro @AlainValette Why so?
Jan 29, 2016 at 16:11 comment added Alain Valette @Fernando: I think you are implicitly assuming that your algebra has a unit.
Jan 29, 2016 at 13:49 review Close votes
Jan 29, 2016 at 20:57
Jan 29, 2016 at 13:44 comment added Fernando Muro I'm using that the algebra has finite dimension so that any f.g. projective module too, over the ground field.
Jan 29, 2016 at 8:25 comment added Ali Taghavi @FernandoMuro where are you using finite dimensionality?As we know there are algebras with finite k group?
Jan 29, 2016 at 7:41 comment added Fernando Muro No, not even removing the word Banach, taking dimension over the ground field defines a surjection onto an infinite cyclic group.
Jan 29, 2016 at 7:36 history edited Ali Taghavi CC BY-SA 3.0
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Jan 29, 2016 at 5:18 history asked Ali Taghavi CC BY-SA 3.0