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arXiv · 2507.08642

Root stack valuative criterion for good moduli spaces

Dori Bejleri·Giovanni Inchiostro·Matthew Satriano
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Abstract

We prove a root stack valuative criterion for good moduli space maps and for gerbes for reductive groups under some mild assumptions on the residue characteristic. We give several applications to parahoric extension for torsors, rational points on stacks, gerbes and homogeneous spaces, and the geometry of fibrations.

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Dori Bejleri, Giovanni Inchiostro, Matthew Satriano. 2025-07-11. Root stack valuative criterion for good moduli spaces. https://arxiv.org/abs/2507.08642

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