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arXiv · 1908.08171

Tropical moduli spaces as symmetric Delta-complexes

Daniel Allcock·Daniel Corey·Sam Payne
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Abstract

We develop techniques for studying fundamental groups and integral singular homology of symmetric Delta-complexes, and apply these techniques to study moduli spaces of stable tropical curves of unit volume, with and without marked points. As one application, we show that Delta_g and Delta_{g,n} are simply connected, for positive g. We also show that Delta_3 is homotopy equivalent to the 5-sphere, and that Delta_4 has 3-torsion in H_5.

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Daniel Allcock, Daniel Corey, Sam Payne. 2019-08-22. Tropical moduli spaces as symmetric Delta-complexes. https://doi.org/10.1112/blms.12570

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