|
Consecutive cancellations in Betti numbers of local rings
Author(s):
Maria Evelina
Rossi;
Leila
Sharifan
Journal:
Proc. Amer. Math. Soc.
138
(2010),
61-73.
MSC (2000):
Primary 13D02
Posted:
August 28, 2009
Retrieve article in:
PDF
Abstract |
References |
Similar articles |
Additional information
Abstract:
Let be a homogeneous ideal in a polynomial ring over a field. By Macaulay's Theorem there exists a lexicographic ideal with the same Hilbert function as Peeva has proved that the Betti numbers of can be obtained from the graded Betti numbers of by a suitable sequence of consecutive cancellations. We extend this result to any ideal in a regular local ring by passing through the associated graded ring. To this purpose it will be necessary to enlarge the list of the allowed cancellations. Taking advantage of Eliahou-Kervaire's construction, we present several applications. This connection between the graded perspective and the local one is a new viewpoint, and we hope it will be useful for studying the numerical invariants of classes of local rings.
References:
-
- [B]
- V. Bertella, Hilbert function of local Artinian level rings in codimension two, J. Algebra 321 (2009), no. 5, 1429-1442.
- [Bi]
- A.M. Bigatti, Upper bounds for the Betti numbers of a given Hilbert function, Comm. Algebra 21 (7) (1993), 2317-2334. MR 1218500 (94c:13014)
- [C]
- CoCoA Team, CoCoA: a system for doing Computations in Commutative Algebra, available at http://cocoa.dima.unige.it.
- [E]
- D. Eisenbud, The Geometry of Syzygies, A Second Course in Commutative Algebra and Algebraic Geometry, Graduate Texts in Mathematics, 229, Springer-Verlag, New York, 2005. MR 2103875 (2005h:13021)
- [EK]
- S. Eliahou, M. Kervaire, Minimal resolutions of some monomial ideals, J. Algebra 129 (1990), no. 1, 1-25. MR 1037391 (91b:13019)
- [EV]
- J. Elias, G. Valla, Structure theorems for certain Gorenstein ideals, Michigan Math. J. 57 (2008), 269-292. MR 2492453
- [HM]
- T. Hibi, S. Murai, The depth of an ideal with a given Hilbert function, Proc. Amer. Math. Soc. 136 (2008), no. 5, 1533-1538. MR 2373580 (2009b:13028)
- [HRV]
- J. Herzog, M. E. Rossi, G. Valla, On the depth of the symmetric algebra, Trans. Amer. Math. Soc. 296 (1986), no. 2, 577-606. MR 846598 (87f:13009)
- [Hu]
- H. A. Hulett, Maximum Betti numbers of homogeneous ideals with a given Hilbert function, Comm. Algebra 21 (1993), no. 7, 2335-2350. MR 1218501 (94c:13015)
- [I]
- A. Iarrobino, Punctual Hilbert schemes, Mem. Amer. Math. Soc. 10, no. 188 (1977). MR 0485867 (58:5667)
- [M]
- F. Macaulay, Some properties of enumeration in the theory of modular systems, Proc. London Math. Soc. 26 (1927), 531-555.
- [P]
- K. Pardue, Deformation classes of graded modules and maximal Betti numbers, Illinois J. Math. 40 (1996), no. 4, 564-585. MR 1415019 (97g:13029)
- [Pe]
- I. Peeva, Consecutive cancellations in Betti numbers, Proc. Amer. Math. Soc. 132 (2004), no. 12, 3503-3507. MR 2084070 (2006a:13023)
- [R]
- L. Robbiano, Coni tangenti a singolaritá razionali, Curve algebriche, Istituto di Analisi Globale, Firenze, 1981.
- [RoV]
- L. Robbiano, G. Valla, On the equations defining tangent cones, Math. Proc. Cambridge Philos. Soc. 88 (1980), no. 2, 281-297. MR 578272 (81i:14004)
- [RSh]
- M. E. Rossi, L. Sharifan, Extremal Betti numbers of filtered modules over a regular local ring, to appear in J. of Algebra, in press.
- [RV]
- M. E. Rossi, G. Valla, Hilbert function of filtered modules, arXiv:0710.2346v1 [math.AC].
- [Sh]
- T. Shibuta, Cohen-Macaulayness of almost complete intersection tangent cones, J. Algebra 319 (8) (2008), 3222-3243. MR 2408315 (2009b:13061)
Similar Articles:
Retrieve articles in Proceedings of the American Mathematical Society
with MSC
(2000):
13D02
Retrieve articles in all Journals with MSC
(2000):
13D02
Additional Information:
Maria Evelina
Rossi
Affiliation:
Department of Mathematics, University of Genoa, Via Dodecaneso 35, 16146 Genoa, Italy
Email:
rossim@dima.unige.it
Leila
Sharifan
Affiliation:
Faculty of Mathematics and Computer Science, Amirkabir University of Technology, 424, Hafez Avenue, 15914 Tehran, Iran
Email:
leila-sharifan@aut.ac.ir
DOI:
10.1090/S0002-9939-09-10010-2
PII:
S 0002-9939(09)10010-2
Keywords:
Minimal free resolution,
filtered module,
associated graded module,
Betti numbers,
lexicographic ideal,
standard bases.
Received by editor(s):
February 11, 2009,
Received by editor(s) in revised form:
April 17, 2009
Posted:
August 28, 2009
Communicated by:
Bernd Ulrich
Copyright of article:
Copyright
2009,
American Mathematical Society
The copyright for this article reverts to public domain after 28 years from publication.
|