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arXiv · 2204.10980

Special cycles for Shtukas are closed

Zhiwei Yun
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Abstract

In this paper we give a different proof of a theorem of Paul Breutmann: for a Bruhat-Tits group scheme $\mathcal{H}$ over a smooth projective curve $X$ and a closed embedding into another smooth affine group scheme $\mathcal{G}$, the induced map on the moduli of Shtukas $Sht^{r}_{\mathcal{H}}\to Sht^{r}_{\mathcal{G}}$ is schematic, finite and unramified. This result enables one to define special cycles on the moduli stack of Shtukas.

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Zhiwei Yun. 2022-04-23. Special cycles for Shtukas are closed. https://arxiv.org/abs/2204.10980

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