{ "id": "1207.0208", "version": "v3", "published": "2012-07-01T13:51:13.000Z", "updated": "2014-07-11T17:07:09.000Z", "title": "Polyhedral divisors and torus actions of complexity one over arbitrary fields", "authors": [ "Kevin Langlois" ], "comment": "We changed the title by a more attractive. No results affected. Final version", "categories": [ "math.AG" ], "abstract": "We show that the presentation of affine $\\mathbb{T}$-varieties of complexity one in terms of polyhedral divisors holds over an arbitrary field. We also describe a class of multigraded algebras over Dedekind domains. We study how the algebra associated to a polyhedral divisor changes when we extend the scalars. As another application, we provide a combinatorial description of affine $\\mathbf{G}$-varieties of complexity one over a field, where $\\mathbf{G}$ is a (not-nescessary split) torus, by using elementary facts on Galois descent. This class of affine $\\mathbf{G}$-varieties is described via a new combinatorial object, which we call (Galois) invariant polyhedral divisor.", "revisions": [ { "version": "v3", "updated": "2014-07-11T17:07:09.000Z" } ], "analyses": { "keywords": [ "arbitrary field", "torus actions", "complexity", "polyhedral divisors holds", "invariant polyhedral divisor" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1207.0208L" } } }