Geometric Weil representation in characteristic two
arXiv:0906.0698 · doi:10.1017/S147474801100017X
Abstract
Let k be an algebraically closed field of characteristic two. Let R be the ring of Witt vectors of length two over k. We construct a group stack \hat G over k, the metaplectic extension of the Greenberg realization of Sp_{2n}(R). We also construct a geometric analog of the Weil representation of \hat G, this is a triangulated category on which \hat G acts by functors. This triangulated category and the action are geometric in a suitable sense.
LaTeX2e, 49 pages, final version to appear in JIMJ