Spherical conic metrics and realizability of branched covers

Zhu, Xuwen

doi:10.1090/proc/14318

Spherical conic metrics and realizability of branched covers
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by Xuwen Zhu

Proc. Amer. Math. Soc. 147 (2019), 1805-1815

DOI: https://doi.org/10.1090/proc/14318

Published electronically: December 6, 2018

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Abstract:

Branched covers between Riemann surfaces are associated with certain combinatorial data, and the Hurwitz existence problem asks whether given data, satisfying those combinatorial constraints can be realized by some branched cover. We connect recent developments in spherical conic metrics to this old problem and give a new method of finding exceptional (unrealizable) branching data. As an application, we find new infinite sets of exceptional branched cover data on the Riemann sphere.

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