2021/12/10 by Tim Gehrunger, Richard Pink, Gehrunger, Tim +1 · 3 citations
Mathematics · #11G20) #14H30 (14H10 #Advanced Algebra and Geometry #Algebraic Geometry (math.AG) #Algebraic Geometry and Number Theory #FOS: Mathematics #Homotopy and Cohomology in Algebraic Topology
paper · pdf · doi:10.48550/arxiv.2112.05550
openalex publication_date 2021/12/10 · openalex created_date 2022/05/05 · openalex updated_date 2026/07/28
Let K be the quotient field of a discrete valuation ring R with residue characteristic \not=2, and let C be a hyperelliptic curve over K. We assume that all geometric branch points of the double covering C\twoheadrightarrow\mathbb P1K are rational and mark both C and \mathbb P1K with these branch points. After possibly replacing R by a ramified extension of degree 2, we give a direct construction for the stable model of C as a marked curve over R. We deduce that the closed fiber of this stable model is determined completely by the closed fiber of the stable model of the marked \mathbb P1K. In particular, the dual graph and other information for the former can be read off directly from the corresponding information for the latter.