Abstract
We prove an isomorphism for simple perverse sheaves on the affine Grassmannian of a connected reductive algebraic group that is a geometric counterpart (in light of the Finkelberg–Mirković conjecture) of the Steinberg tensor product formula for simple representations of reductive groups over fields of positive characteristic.
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Dedicated to the memory of Jim Humphreys
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Pramod N. Achar is supported by NSF Grant No. DMS-1802241.
Simon Riche this project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreements No 677147 and 101002592).
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ACHAR, P.N., RICHE, S. A GEOMETRIC STEINBERG FORMULA. Transformation Groups 28, 1001–1032 (2023). https://doi.org/10.1007/s00031-022-09768-y
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DOI: https://doi.org/10.1007/s00031-022-09768-y