On Toric Face Rings
نویسنده
چکیده
Following a construction of Stanley we consider toric face rings associated to rational pointed fans. This class of rings is a common generalization of the concepts of Stanley–Reisner and affine monoid algebras. The main goal of this article is to unify parts of the theories of Stanley–Reisnerand affine monoid algebras. We consider (nonpure) shellable fan’s and the Cohen–Macaulay property. Moreover, we study the local cohomology, the canonical module and the Gorenstein property of a toric face ring.
منابع مشابه
Dualizing Complex of a Toric Face Ring Ii: Non-normal Case
The notion of toric face rings generalizes both Stanley-Reisner rings and affine semigroup rings, and has been studied by Bruns, Römer, et.al. Here, we will show that, for a toric face ring R, the “graded” Matlis dual of a Cěch complex gives a dualizing complex. In the most general setting, R is not a graded ring in the usual sense. Hence technical argument is required.
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