Models of hypersurfaces and Bruhat-Tits buildings
Abstract
We propose a new approach to constructing semistable integral models of hypersurfaces over a discretely valued complete field K. For each stable hypersurface X over K we define a continuous stability function on the Bruhat-Tits building of PGL_{n+1}(K); its global minima control semistable hypersurface models after finite extensions of K. In particular, in residue characteristic zero the problem reduces to minimizing this function on the original building and then passing to a finite extension that turns a rational minimizer into a vertex. This extends work of Kollar and of Elsenhans-Stoll on minimal hypersurface models. We implement the resulting strategy for plane curves over p-adic number fields. In a follow-up article we use our results to compute the semistable reduction of smooth plane quartics.
Keywords
Cite
@article{arxiv.2501.02638,
title = {Models of hypersurfaces and Bruhat-Tits buildings},
author = {Kletus Stern and Stefan Wewers},
journal= {arXiv preprint arXiv:2501.02638},
year = {2026}
}
Comments
37 pages, 4 figures, Major revision. Added a formulation of the tame case (Theorem 1.7), clarified the role of the stability function and its minima, and included a detailed discussion of the algorithm and its implementation