English

An explicit wall crossing for the moduli space of hyperplane arrangements

Algebraic Geometry 2025-05-07 v2

Abstract

The moduli space of hyperplanes in projective space has a family of geometric and modular compactifications that parametrize stable hyperplane arrangements with respect to a weight vector. Among these, there is a toric compactification that generalizes the Losev-Manin moduli space of points on the line. We study the first natural wall crossing that modifies this compactification into a non-toric one by varying the weights. As an application of our work, we show that any Q\mathbb{Q}-factorialization of the blow up at the identity of the torus of the generalized Losev-Manin space is not a Mori dream space for a sufficiently high number of hyperplanes. Additionally, for lines in the plane, we provide a precise description of the wall crossing.

Keywords

Cite

@article{arxiv.2405.09051,
  title  = {An explicit wall crossing for the moduli space of hyperplane arrangements},
  author = {Patricio Gallardo and Luca Schaffler},
  journal= {arXiv preprint arXiv:2405.09051},
  year   = {2025}
}

Comments

26 pages, 5 figures. Final version. To appear in Journal of the London Mathematical Society