On the topology of the moduli of tropical unramified p-covers

Yassine El Maazouz; Paul Alexander Helminck; Felix Röhrle; Pedro Souza; Claudia He Yun

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arXiv · 2403.06624

On the topology of the moduli of tropical unramified p-covers

Yassine El Maazouz·Paul Alexander Helminck·Felix Röhrle·Pedro Souza·Claudia He Yun

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Abstract

We study the topology of the moduli space of unramified $\mathbb{Z}/p$-covers of tropical curves of genus $g \geq 2$, where $p$ is a prime number. We use recent techniques by Chan--Galatius--Payne to identify contractible subcomplexes of the moduli space. We then use this contractibility result to show that this moduli space is simply connected. In the case of genus 2, we determine the homotopy type of this moduli space for all primes $p$. This work is motivated by prospective applications to the top-weight cohomology of the space of prime cyclic \'etale covers of smooth algebraic curves.

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Yassine El Maazouz, Paul Alexander Helminck, Felix Röhrle, Pedro Souza, Claudia He Yun. 2024-03-11. On the topology of the moduli of tropical unramified p-covers. https://arxiv.org/abs/2403.06624

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