Base change and the Mackey formula in Deligne--Lusztig theory

Sean Cotner

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arXiv · 2609.22331

Base change and the Mackey formula in Deligne--Lusztig theory

Sean Cotner

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Abstract

Using ideas of Digne and recent work of Gaitsgory--Rozenblyum--Varshavsky, we show that Lusztig induction commutes with (a minor variant of) the Glauberman correspondence for large prime degree field extensions. This allows one to reduce the Mackey formula in Deligne--Lusztig theory to the case of ``large'' base fields, in which case the result is due to Bonnafé.

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BibTeX RIS

Sean Cotner. 2026-09-16. Base change and the Mackey formula in Deligne--Lusztig theory. https://arxiv.org/abs/2609.22331

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