Logarithmic Hilbert schemes of curves as weighted blow-ups and their integral Chow rings

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Arena, Veronica, Song, Terry Dekun
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916022493118464
author Arena, Veronica
Song, Terry Dekun
author_facet Arena, Veronica
Song, Terry Dekun
contents The logarithmic Hilbert scheme of a logarithmic curve parametrizes subschemes on the expanded degenerations of the curve that are transverse to the boundary. We prove that the logarithmic Hilbert scheme of points on a smooth pointed curve is an iterated weighted blow-up of the symmetric product of the underlying curve. In doing so, we explicitly identify the blow-up centers, weights, and give them modular interpretations. As applications, we calculate their integral Chow rings in terms of those of the symmetric products. Key ingredients in our work include two recent results: the integral Chow ring formula of weighted blow-ups and a weighted analogue of Castelnuovo's criterion for blow-downs. We recover the folklore result the logarithmic Hilbert scheme of toric $\mathbb{P}^1$ is a toric stack, and the Appendix by Dhruv Ranganathan outlines a complementary approach using Chow quotients.
format Preprint
id arxiv_https___arxiv_org_abs_2605_17922
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Logarithmic Hilbert schemes of curves as weighted blow-ups and their integral Chow rings
Arena, Veronica
Song, Terry Dekun
Algebraic Geometry
14D23, 14C15
The logarithmic Hilbert scheme of a logarithmic curve parametrizes subschemes on the expanded degenerations of the curve that are transverse to the boundary. We prove that the logarithmic Hilbert scheme of points on a smooth pointed curve is an iterated weighted blow-up of the symmetric product of the underlying curve. In doing so, we explicitly identify the blow-up centers, weights, and give them modular interpretations. As applications, we calculate their integral Chow rings in terms of those of the symmetric products. Key ingredients in our work include two recent results: the integral Chow ring formula of weighted blow-ups and a weighted analogue of Castelnuovo's criterion for blow-downs. We recover the folklore result the logarithmic Hilbert scheme of toric $\mathbb{P}^1$ is a toric stack, and the Appendix by Dhruv Ranganathan outlines a complementary approach using Chow quotients.
title Logarithmic Hilbert schemes of curves as weighted blow-ups and their integral Chow rings
topic Algebraic Geometry
14D23, 14C15
url https://arxiv.org/abs/2605.17922