Virtual resolutions of points in $\mathbb{P}^1 \times \mathbb{P}^1$
Abstract
We explore explicit virtual resolutions, as introduced by Berkesch, Erman,
and Smith, for ideals of sets of points in $\mathbb{P}^1 \times \mathbb{P}^1$.
Specifically, we describe a virtual resolution for a sufficiently general set
of points $X$ in $\mathbb{P}^1 \times \mathbb{P}^1$ that only depends on $|X|$.
We also improve an existence result of Berkesch, Erman, and Smith in the
special case of points in $\mathbb{P}^1 \times \mathbb{P}^1$; more precisely,
we give an effective bound for their construction that gives a virtual
resolution of length two for any set of points in $\mathbb{P}^1 \times
\mathbb{P}^1$.