Moduli of Distributions via Singular Schemes

Maurício Corrêa, Marcos Jardim, Alan Muniz

Published 2020-10-05Version 1

Let $X$ be a smooth projective variety with $\operatorname{Pic}(X) \simeq \mathbb{Z}$. We show that the map that sends a codimension one distribution on $X$ to its singular scheme is a morphism from the moduli space of distributions into a Hilbert scheme. We describe its fibers and, when $X = \mathbb{P}^n$, compute them via syzygies. As an application, we describe the moduli spaces of degree 1 distributions on $\mathbb{P}^3$. We also give the minimal graded free resolution for the ideal of the singular scheme of a generic distribution on $\mathbb{P}^3$.