{ "id": "1607.03472", "version": "v1", "published": "2016-07-12T19:34:35.000Z", "updated": "2016-07-12T19:34:35.000Z", "title": "The automorphism group of a rigid affine variety", "authors": [ "Ivan Arzhantsev", "Sergey Gaifullin" ], "comment": "10 pages", "categories": [ "math.AG" ], "abstract": "An algebraic variety $X$ is rigid if it admits no nontrivial action of the additive group of the ground field. We prove that the automorphism group $\\text{Aut}(X)$ of a rigid affine variety contains a unique maximal torus $\\mathbb{T}$. If the grading on the algebra of regular functions $\\mathbb{K}[X]$ defined by the action of $\\mathbb{T}$ is pointed, the group $\\text{Aut}(X)$ is a finite extension of $\\mathbb{T}$. As an application, we describe the automorphism group of a rigid trinomial affine hypersurface and find all isomorphisms between such hypersurfaces.", "revisions": [ { "version": "v1", "updated": "2016-07-12T19:34:35.000Z" } ], "analyses": { "subjects": [ "14J50", "14R20", "13A50", "14L30" ], "keywords": [ "automorphism group", "rigid affine variety contains", "rigid trinomial affine hypersurface", "unique maximal torus", "ground field" ], "note": { "typesetting": "TeX", "pages": 10, "language": "en", "license": "arXiv", "status": "editable" } } }