Open AccessJournal Article
Castelnuovo-Mumford regularity of products of ideals
Aldo Conca,Herzog Jürgen +1 more
TLDR
In this article, it was shown that the Castelnuovo-Mumford regularity of a module can be doubly exponential in the degrees of the minimal generators and in the number of variables.Abstract:
The Castelnuovo-Mumford regularity reg$(M)$ is one of the most important invariants of a finitely generated graded module $M$ over a polynomial ring $R$. For instance, it measures the amount of computational resources that working with $M$ requires. In general one knows that the regularity of a module can be doubly exponential in the degrees of the minimal generators and in the number of the variables. On the other hand, in many situations one has or one conjectures a much better behavior. One may ask, for instance, whether the Castelnuovo-Mumford regularity reg($IM$) of the product of an ideal $I$ with a module $M$ is bounded by the sum reg($I$) + reg($M$). In general this is not the case. But we show that it is indeed the case if either dim $R/I\leq 1$ or $I$ is generic (in a very precise sense). Further we show that products of ideals of linear forms have always a linear resolution and that the same is true for products of determinantal ideals of a generic Hankel matrix.read more
Citations
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The depth of powers of an ideal
Juergen Herzog,Takayuki Hibi +1 more
TL;DR: In this article, the limit and initial behavior of the numerical function f (k ) = depth S / I k were studied and general properties of this function together with concrete examples arising from combinatorics were discussed.
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How to compute the Stanley depth of a monomial ideal
TL;DR: In this article, it was shown that the f-depth of a monomial ideal can also be computed in a finite number of steps, and that these invariants can be determined by partitioning suitable finite posets into intervals.
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Monomial ideals whose powers have a linear resolution
TL;DR: In this paper, the authors consider graded ideals in a polynomial ring over a field and ask when such an ideal has the property that all of its powers have a linear resolution.
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The regularity of Tor and graded Betti Numbers
TL;DR: In this paper, the authors give bounds for the regularity of the local cohomology of Tork (A, B) in terms of the graded Betti numbers of A and B, under the assumption that dim Tor1 ≤ 1, and apply the results to syzygies, Grobner bases, products and powers of ideals.
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The stable set of associated prime ideals of a polymatroidal ideal
TL;DR: The associated prime ideals of powers of polymatroidal ideals are studied in this paper, including the stable set of associated prime ideal ideals of this class of ideals, and it is shown that polymatoidal ideals have the persistence property and for transversal polymatroids, the index of stability and associated ideals are determined explicitly.
References
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Book
Commutative Algebra: with a View Toward Algebraic Geometry
TL;DR: In this article, the authors define basic constructions and dimension theory, and apply them to the problem of homological methods for combinatorial problem solving in the context of homology.
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Cohen-Macaulay rings
Winfried Bruns,H. Jürgen Herzog +1 more
TL;DR: In this article, the authors present a self-contained introduction to the homological and combinatorial aspects of the theory of Cohen-Macaulay rings, Gorenstein rings, local cohomology, and canonical modules.
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Asymptotic Behaviour of the Castelnuovo-Mumford Regularity
TL;DR: In this paper, the asymptotic behavior of the Castelnuovo norm and the Mumford norm of the integral closure of the powers of a homogeneous ideal I is studied.
Journal ArticleDOI
Asymptotic behaviour of Castelnuovo-Mumford regularity
TL;DR: In this article, it was shown that the Castelnuovo-Mumford regularity of a polynomial ring over a field is bounded by a linear function with leading coefficient at most P.