nLab enhanced triangulated category



Homological algebra

homological algebra

(also nonabelian homological algebra)



Basic definitions

Stable homotopy theory notions



diagram chasing

Schanuel's lemma

Homology theories


Stable homotopy theory



Any stable (∞,1)-category CC gives rise to a canonical triangulated category ho(C)ho(C), its homotopy category. Much of the information contained in CC is still present in ho(C)ho(C), so that in many situations it can be enough to work at the level of triangulated categories. However, in general various problems with triangulated categories require one to work with some sort of higher structure lying above ho(C)ho(C). Such a structure is often called an enhancement of the triangulated category ho(C)ho(C).

Examples of enhanced triangulated categories are, in order of increasing information:


After Jean-Louis Verdier started the development of the theory of triangulated categories in his 1963 thesis, it was quickly recognized that some sort of enhancements were necessary to get the full picture. For this purpose, Alexandre Grothendieck suggested the notion of derivator in the early 1980’s, while Alexei Bondal and Mikhail Kapranov developed the notion of pretriangulated dg-category in 1990. In 2006 Jacob Lurie developed the notion of stable (∞,1)-category.

Problems with triangulated categories

(to be expanded on)

Comparison results

In (Cohn 13) it is shown that the (∞,1)-category of idempotent complete pretriangulated dg-categories over a commutative ring kk is equivalent to the (∞,1)-category of stable k-linear (∞,1)-categories. See pretriangulated dg-category for details.

In (Renaudin 2006) it is shown that the 2-category of locally presentable derivators is equivalent to the localization of the 2-category of combinatorial model categories at the Quillen equivalences. Combinatorial model categories are equivalent to locally presentable (∞,1)-categories in a sense made precise there. However, a comparison between the stability conditions in the derivator and (∞,1)-category settings seems still to be open.


Brief overview and list of further references:

Last revised on September 17, 2022 at 15:59:37. See the history of this page for a list of all contributions to it.