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arXiv · 2411.07169

Distinguishing Algebraic Spaces from Schemes

Andres Fernandez Herrero·Dario Weißmann·Xucheng Zhang
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Abstract

We introduce local invariants of algebraic spaces and stacks which measure how far they are from being a scheme. Using these invariants, we develop mostly topological criteria to determine when the moduli space of a stack is a scheme. As an application we study moduli of principal bundles on a smooth projective curve.

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Andres Fernandez Herrero, Dario Weißmann, Xucheng Zhang. 2024-11-11. Distinguishing Algebraic Spaces from Schemes. https://arxiv.org/abs/2411.07169

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