{ "id": "0810.0794", "version": "v3", "published": "2008-10-05T01:13:58.000Z", "updated": "2013-01-07T18:45:23.000Z", "title": "Character sheaves on unipotent groups in positive characteristic: foundations", "authors": [ "Mitya Boyarchenko", "Vladimir Drinfeld" ], "comment": "106 pages, LaTeX; to appear in Selecta Mathematica", "categories": [ "math.RT" ], "abstract": "In this article we formulate and prove the main theorems of the theory of character sheaves on unipotent groups over an algebraically closed field of characteristic p>0. In particular, we show that every admissible pair for such a group G gives rise to an L-packet of character sheaves on G, and that, conversely, every L-packet of character sheaves on G arises from a (non-unique) admissible pair. In the appendices we discuss two abstract category theory patterns related to the study of character sheaves. The first appendix sketches a theory of duality for monoidal categories, which generalizes the notion of a rigid monoidal category and is close in spirit to the Grothendieck-Verdier duality theory. In the second one we use a topological field theory approach to define the canonical braided monoidal structure and twist on the equivariant derived category of constructible sheaves on an algebraic group; moreover, we show that this category carries an action of the surface operad. The third appendix proves that the \"naive\" definition of the equivariant constructible derived category with respect to a unipotent algebraic group is equivalent to the \"correct\" one.", "revisions": [ { "version": "v3", "updated": "2013-01-07T18:45:23.000Z" } ], "analyses": { "keywords": [ "character sheaves", "unipotent groups", "positive characteristic", "category theory patterns", "foundations" ], "note": { "typesetting": "LaTeX", "pages": 106, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2008arXiv0810.0794B" } } }