{ "id": "2108.03584", "version": "v1", "published": "2021-08-08T07:54:12.000Z", "updated": "2021-08-08T07:54:12.000Z", "title": "The supersingular locus of the Shimura variety of $\\mathrm{GU}(2,n-2)$", "authors": [ "Maria Fox", "Naoki Imai" ], "comment": "28 pages", "categories": [ "math.NT", "math.AG" ], "abstract": "We study the supersingular locus of a reduction at an inert prime of the Shimura variety attached to $\\mathrm{GU}(2,n-2)$. More concretely, we realize irreducible components of the supersingular locus as closed subschemes of flag schemes over Deligne--Lusztig varieties defined by explicit conditions. Moreover we study the intersections of the irreducible components. A stratification of Deligne--Lusztig varieties defined using a power of Frobenius action appears in the description of the intersections.", "revisions": [ { "version": "v1", "updated": "2021-08-08T07:54:12.000Z" } ], "analyses": { "subjects": [ "11G18", "14M15" ], "keywords": [ "supersingular locus", "shimura variety", "deligne-lusztig varieties", "frobenius action appears", "inert prime" ], "note": { "typesetting": "TeX", "pages": 28, "language": "en", "license": "arXiv", "status": "editable" } } }