Newton polygons and curve gonalities
نویسندگان
چکیده
We give a combinatorial upper bound for the gonality of a curve that is defined by a bivariate Laurent polynomial with given Newton polygon. We conjecture that this bound is generically attained, and provide proofs in a considerable number of special cases. One proof technique uses recent work of M. Baker on linear systems on graphs, by means of which we reduce our conjecture to a purely combinatorial statement.
منابع مشابه
Erratum to: Newton polygons and curve gonalities
We have made a conceptual error in the construction of our regular strongly semistable arithmetic surface X over C[[t]], as explained in [2, Sect. 7]. The error lies in the last part, involving toric resolutions of singularities. Namely, it has been overlooked that the exceptional curves that are introduced during the resolution may appear with non-trivial multiplicities, turning X non-stable. ...
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