{ "id": "2201.00033", "version": "v2", "published": "2021-12-31T19:18:17.000Z", "updated": "2022-11-09T19:34:14.000Z", "title": "Weierstrass semigroups from cyclic covers of hyperelliptic curves", "authors": [ "Ethan Cotterill", "Nathan Pflueger", "Naizhen Zhang" ], "comment": "31 pages. Revised version now includes explicit effective calculations for a distinguished class of \"staircase\" semigroups; submitted", "categories": [ "math.AG", "math.CO", "math.NT" ], "abstract": "The {\\it Weierstrass semigroup} of pole orders of meromorphic functions in a point $p$ of a smooth algebraic curve $C$ is a classical object of study; a celebrated problem of Hurwitz is to characterize which semigroups ${\\rm S} \\subset \\mathbb{N}$ with finite complement are {\\it realizable} as Weierstrass semigroups ${\\rm S}= {\\rm S}(C,p)$. In this note, we establish realizability results for cyclic covers $\\pi: (C,p) \\rightarrow (B,q)$ of hyperelliptic targets $B$ marked in hyperelliptic Weierstrass points; and we show that realizability is dictated by the behavior under $j$-fold multiplication of certain divisor classes in hyperelliptic Jacobians naturally associated to our cyclic covers, as $j$ ranges over all natural numbers.", "revisions": [ { "version": "v2", "updated": "2022-11-09T19:34:14.000Z" } ], "analyses": { "subjects": [ "14H10", "14H30", "14H40", "14H45", "14H51", "14Gxx" ], "keywords": [ "cyclic covers", "weierstrass semigroup", "hyperelliptic curves", "smooth algebraic curve", "hyperelliptic weierstrass points" ], "note": { "typesetting": "TeX", "pages": 31, "language": "en", "license": "arXiv", "status": "editable" } } }