{ "id": "2410.15598", "version": "v1", "published": "2024-10-21T02:45:42.000Z", "updated": "2024-10-21T02:45:42.000Z", "title": "Rost injectivity for classical groups over function fields of curves over local fields", "authors": [ "R. Parimala", "V. Suresh" ], "comment": "23 pages", "categories": [ "math.NT", "math.AG", "math.RA" ], "abstract": "Let F be a complete discretely valued field with residue field a global field or a local field with no real orderings. Let G be an absolutely simple simply connected group of outer type A_n. If 2 and the index of the underlying algebra of G are coprime to the characteristic of the residue field of F, then we prove that the Rost invariant map from the first Galois cohomology set of G to the degree three Galois cohomology group is injective. Let L be the function field of a curve over a local field K and G an absolutely simple simply connected linear algebraic group over L of classical type. Suppose that the characteristic of the residue field of K is a good prime for G. As a consequence of our result and some known results we conclude that the Rost invariant of G is injective.", "revisions": [ { "version": "v1", "updated": "2024-10-21T02:45:42.000Z" } ], "analyses": { "subjects": [ "11E57", "11E39" ], "keywords": [ "local field", "function field", "rost injectivity", "connected linear algebraic group", "classical groups" ], "note": { "typesetting": "TeX", "pages": 23, "language": "en", "license": "arXiv", "status": "editable" } } }