Additions to a theorem of Morey-Ulrich

Abstract

Let $R=k[x_1,\dots ,x_d]$ denote a standard graded polynomial ring over an algebraically closed field $k$, and let $I\subset R$ be a perfect ideal of codimension $2$ with an $n\times (n-1)$ linear presentation matrix $\varphi$. We prove an extended formulation of a theorem of Morey and Ulrich in the case where $I$ satisfies condition $G_{d-1}$, but not condition $G_d$.

In this version, we've made several changes to the article's introduction and exposition. We've corrected some typos found in the previous version