{ "id": "1906.10672", "version": "v1", "published": "2019-06-25T17:10:04.000Z", "updated": "2019-06-25T17:10:04.000Z", "title": "Local-global principles for tori over arithmetic curves", "authors": [ "Jean-Louis Colliot-Thélène", "David Harbater", "Julia Hartmann", "Daniel Krashen", "R. Parimala", "V. Suresh" ], "comment": "27 pages", "categories": [ "math.AG", "math.NT" ], "abstract": "In this paper we study local-global principles for tori over semi-global fields, which are one variable function fields over complete discretely valued fields. In particular, we show that for principal homogeneous spaces for tori over the underlying discrete valuation ring, the obstruction to a local-global principle with respect to discrete valuations can be computed using methods coming from patching. We give a sufficient condition for the vanishing of the obstruction, as well as examples were the obstruction is nontrivial or even infinite. A major tool is the notion of a flasque resolution of a torus.", "revisions": [ { "version": "v1", "updated": "2019-06-25T17:10:04.000Z" } ], "analyses": { "subjects": [ "11E72", "12G05", "14G05", "14H25", "20G15", "14G27" ], "keywords": [ "arithmetic curves", "discrete valuation", "obstruction", "study local-global principles", "variable function fields" ], "note": { "typesetting": "TeX", "pages": 27, "language": "en", "license": "arXiv", "status": "editable" } } }