{ "id": "0709.1710", "version": "v3", "published": "2007-09-11T20:05:32.000Z", "updated": "2008-09-11T16:15:28.000Z", "title": "Symmetries and exotic smooth structures on a $K3$ surface", "authors": [ "Weimin Chen", "Slawomir Kwasik" ], "comment": "46 pages, final version, Journal of Topology, to appear", "categories": [ "math.GT", "math.SG" ], "abstract": "Smooth and symplectic symmetries of an infinite family of distinct exotic $K3$ surfaces are studied, and comparison with the corresponding symmetries of the standard $K3$ is made. The action on the $K3$ lattice induced by a smooth finite group action is shown to be strongly restricted, and as a result, nonsmoothability of actions induced by a holomorphic automorphism of a prime order $\\geq 7$ is proved and nonexistence of smooth actions by several $K3$ groups is established (included among which is the binary tetrahedral group $T_{24}$ which has the smallest order). Concerning symplectic symmetries, the fixed-point set structure of a symplectic cyclic action of a prime order $\\geq 5$ is explicitly determined, provided that the action is homologically nontrivial.", "revisions": [ { "version": "v3", "updated": "2008-09-11T16:15:28.000Z" } ], "analyses": { "subjects": [ "57S15", "57R55", "57R17" ], "keywords": [ "exotic smooth structures", "smooth finite group action", "symplectic symmetries", "prime order", "symplectic cyclic action" ], "note": { "typesetting": "TeX", "pages": 46, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2007arXiv0709.1710C" } } }