Dualizing complex of the incidence algebra of a finite regular cell complex
Abstract
Let be a finite regular cell complex with , and regard it as a partially ordered set (poset) by inclusion. Let be the incidence algebra of the poset over a field . Corresponding to the Verdier duality for constructible sheaves on , we have a dualizing complex giving a duality functor from to itself. satisfies the Auslander condition. Our duality is somewhat analogous to the Serre duality for projective schemes ( plays a similar role to that of "irrelevant ideals"). If for exactly one , then the underlying topological space of is Cohen-Macaulay (in the sense of the Stanley-Reisner ring theory). The converse also holds when is a simplicial complex. is always a Koszul ring with . The relation between the Koszul duality for and the Verdier duality is discussed. This result is a variant of a theorem of Vybornov. The Mobius function of the poset is also discussed.
Keywords
Cite
@article{arxiv.math/0407383,
title = {Dualizing complex of the incidence algebra of a finite regular cell complex},
author = {Kohji Yanagawa},
journal= {arXiv preprint arXiv:math/0407383},
year = {2007}
}
Comments
18 pages. The results are almost same. But the exposition has been totally revised emphasizing combinatorial aspects