Parabolic geometric Eisenstein series and constant term functors
Representation Theory
2025-07-30 v2 Algebraic Geometry
Abstract
We prove a compatibility between parabolic restriction of Whittaker sheaves and restriction of representations under the geometric Casselman-Shalika equivalence. To do this, we establish various Hecke structures on geometric Eisenstein series functors, generalizing results of Braverman-Gaitsgory in the case of a principal parabolic. Moreover, we relate compactified and non-compactified geometric Eisenstein series functors via Koszul duality. We sketch a proof that the spectral-to-automorphic geometric Langlands functor commutes with constant term functors.
Cite
@article{arxiv.2507.13930,
title = {Parabolic geometric Eisenstein series and constant term functors},
author = {Joakim Faergeman and Andreas Hayash},
journal= {arXiv preprint arXiv:2507.13930},
year = {2025}
}
Comments
Minor edits to the introduction and acknowledgements section. Comments are very welcome!