Skip to main content
4 events
when toggle format what by license comment
Sep 26, 2015 at 17:46 comment added Nuno I may be missing something simple, but to justify your last sentence shouldn't we require that the triangulated category is Karoubian?
Jul 11, 2011 at 22:45 comment added David E Speyer In my experience (coming mostly from the quiver theory literature), this definition isn't popular because there are very few monomorphisms in the derived category. For example, if $R$ is a ring, and $0 \to M_1 \to M_2 \to M_3 \to 0$ is a non-split s.e.s. of $R$-modules, then $M_1 \to M_2$ is not a monomorphism in the derived category of $R$-modules. In my reading, Sasha's definition is the standard one.
Jul 11, 2011 at 19:28 comment added Ralph Good explanation. It seems to me, this definition even works in every category with a zero object, not just abelian categories. But perhaps I'm missing something ?
Jul 11, 2011 at 17:55 history answered Neil Strickland CC BY-SA 3.0