Generalized local cohomology and regularity of Ext modules
| dc.creator | Chardin, Marc | |
| dc.creator | Divaani-Aazar, Kamran | |
| dc.date | 2007-01-18 | |
| dc.date | 2007-06-19 | |
| dc.date.accessioned | 2026-07-07T08:10:55Z | |
| dc.date.available | 2026-07-07T08:10:55Z | |
| dc.description | Let R be a Noetherian standard graded ring, and M and N two finitely generated graded R-modules. We introduce reg_R (M,N) by using the notion of generalized local cohomology instead of local cohomology, in the definition of regularity. We prove that reg_R (M,N)is finite in several cases. In the case that the base ring is a field, we show that reg_R (M,N)=reg (N)-indeg (M). This formula, together with a graded version of duality for generalized local cohomology, gives a formula for the minimum of the initial degrees of some Ext modules(in the case R is Cohen-Macaulay), of which the three usual definitions of regularity are special cases. Bounds for regularity of certain Ext modules are obtained, using the same circle of ideas. | |
| dc.description | 17 pages, contains some addings and corrections | |
| dc.identifier | https://arxiv.org/abs/math/0701509 | |
| dc.identifier | http://arxiv.org/abs/math/0701509 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/131960 | |
| dc.subject | Commutative Algebra | |
| dc.subject | 13D02;13D45 | |
| dc.title | Generalized local cohomology and regularity of Ext modules | |
| dc.type | text |