On the unramified Eisenstein spectrum

David Kazhdan; Andrei Okounkov

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arXiv · 2203.03486

On the unramified Eisenstein spectrum

David Kazhdan·Andrei Okounkov

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Abstract

For a split reductive group ${}^L G$ over a global field, we determine the spectrum of the spherical Hecke algebra coming from the unramified Eisenstein series for the minimal parabolic ${}^L B$. This is done using a certain decomposition of the Springer stack $T^*(B \backslash G/ B)$ for the Langlands dual group in the additive group of cobordisms of cohomologically proper derived quotient stacks.

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David Kazhdan, Andrei Okounkov. 2022-03-03. On the unramified Eisenstein spectrum. https://arxiv.org/abs/2203.03486

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