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arXiv · 2510.23207

The Shimurian BT stack is a gerbe over truncated displays

Eike Lau
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Abstract

We show that the mod $p$ fiber of the Shimurian stack $BT_n^{G,\mu}$ constructed by Gardner--Madapusi is a gerbe over the corresponding stack of truncated displays. This confirms a conjecture of Drinfeld.

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Eike Lau. 2025-10-27. The Shimurian BT stack is a gerbe over truncated displays. https://arxiv.org/abs/2510.23207

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