English

Equations of Rees algebras of ideals in two variables

Commutative Algebra 2015-11-16 v1 Algebraic Geometry

Abstract

Let I be an ideal of height two in R=k[x_0,x_1] generated by forms of the same degree, and let K be the ideal of defining equations of the Rees algebra of I. Suppose that the second largest column degree in the syzygy matrix of I is e. We give an algorithm for computing the minimal generators of K whose degree is at least e, as well as a simple formula for the bidegrees of these generators. In the case where I is an almost complete intersection, we give a generating set for each graded piece K_(i,*) with i>=e-1.

Keywords

Cite

@article{arxiv.1511.04073,
  title  = {Equations of Rees algebras of ideals in two variables},
  author = {Jeff Madsen},
  journal= {arXiv preprint arXiv:1511.04073},
  year   = {2015}
}