arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1111.0279math.ACmath.AG
收藏

自由分解与稀疏行列式理想

Free Resolutions and Sparse Determinantal Ideals

Adam Boocher

摘要:

稀疏通用矩阵是其元素是不同变量和零的矩阵。Giusti和Merle研究了此类矩阵,他们计算了极大子式理想的一些不变量。在本文中,我们通过计算所有这样的稀疏行列式理想的最小自由分解来扩展这些结果。我们这样做时,引入了一种技术修剪最小的自由分解的变量的子集被设置为零。我们的技术正确地计算一个最小的自由分解在两种情况下的利益:决议的单项式的理想,理想解决的Wisconon-Northcott复杂。因此,我们可以证明稀疏行列式理想在整数上有线性分解,并且投射维数仅取决于矩阵中同为零的列数。最后,我们证明了所有这样的理想的性质,无论选择的术语顺序,贝蒂数的理想和它的初始理想是相同的。特别是这些理想的非零生成元形成了一个普遍的Gröbner基。

英文摘要:

A sparse generic matrix is a matrix whose entries are distinct variables and zeros. Such matrices were studied by Giusti and Merle who computed some invariants of their ideals of maximal minors. In this paper we extend these results by computing a minimal free resolution for all such sparse determinantal ideals. We do so by introducing a technique for pruning minimal free resolutions when a subset of the variables is set to zero. Our technique correctly computes a minimal free resolution in two cases of interest: resolutions of monomial ideals, and ideals resolved by the Eagon-Northcott Complex. As a consequence we can show that sparse determinantal ideals have a linear resolution over the integers, and that the projective dimension depends only on the number of columns of the matrix which are identically zero. Finally, we show that all such ideals have the property that regardless of the term order chosen, the Betti numbers of the ideal and its initial ideal are the same. In particular the nonzero generators of these ideals form a universal Gröbner basis.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑