SOME 4-POINT HURWITZ NUMBERS IN POSITIVE CHARACTERISTIC

被引：2

作者：

Bouw, Irene I. ^{[1
]}

Osserman, Brian ^{[2
]}

机构：

[1] Univ Ulm, Dept Math, D-89069 Ulm, Germany

[2] Univ Calif Davis, Dept Math, Davis, CA 95616 USA

来源：

TRANSACTIONS OF THE AMERICAN MATHEMATICAL SOCIETY | 2011年 / 363卷 / 12期

关键词：

FINITE SIMPLE-GROUPS; METACYCLIC COVERS; REDUCTION; CURVES; SPACES;

D O I：

10.1090/S0002-9947-2011-05347-X

中图分类号：

O1 [数学];

学科分类号：

0701 ; 070101 ;

摘要：

In this paper, we compute the number of covers of curves with given branch behavior in characteristic p for one class of examples of genus 0, with four branch points and degree p. Our techniques involve related computations in the case of three branch points, and allow us to conclude in many cases that for a particular choice of degeneration, all the covers we consider degenerate to separable (admissible) covers. Starting from a good understanding of the complex case, the proof is centered on the theory of stable reduction of Galois covers.

引用

页码：6685 / 6711

页数：27

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