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arXiv · 2308.12195

A motivic Fundamental Lemma

Arthur Forey·François Loeser·Dimitri Wyss
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Abstract

In this paper we prove motivic versions of the Langlands-Shelstad Fundamental Lemma and Ngô's Geometric Stabilization. To achieve this, we follow the strategy from the recent proof by Groechenig, Wyss and Ziegler which avoided the use of perverse sheaves using instead $p$-adic integration and Tate duality. We make a key use of a construction of Denef and Loeser which assigns a virtual motive to any definable set in the theory of pseudo-finite fields.

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BibTeXRIS

Arthur Forey, François Loeser, Dimitri Wyss. 2026-07-31. A motivic Fundamental Lemma. https://doi.org/10.2140/gt.2026.30.2043

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