Spherical conic metrics and realizability of branched covers

Xuwen Zhu

doi:10.1090/proc/14318

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arXiv · 1805.03312

Spherical conic metrics and realizability of branched covers

Xuwen Zhu

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Abstract

Branched covers between Riemann surfaces are associated with certain combinatorial data, and Hurwitz existence problem asks whether given data satisfying those combinatorial constraints can be realized by some branched cover. We connect recent development 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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Xuwen Zhu. 2018-05-08. Spherical conic metrics and realizability of branched covers. https://doi.org/10.1090/proc/14318

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