{ "id": "1202.2398", "version": "v3", "published": "2012-02-11T01:55:20.000Z", "updated": "2013-05-19T14:40:46.000Z", "title": "The Pompeiu Problem and Discrete Groups", "authors": [ "Michael J. Puls" ], "comment": "Version two fixes some typos. Also a new section was added concerning the harmonicity of a function with regards to the mean-value property on two spheres. Corrected some more typos", "categories": [ "math.FA", "math.GR" ], "abstract": "We formulate a version of the Pompeiu problem in the discrete group setting. Necessary and sufficient conditions are given for a finite collection of finite subsets of a discrete abelian group, whose torsion free rank is less than the cardinal of the continuum, to have the Pompeiu property. We also prove a similar result for nonabelian free groups. A sufficient condition is given that guarantees the harmonicity of a function on a nonabelian free group if it satisfies the mean-value property over two spheres.", "revisions": [ { "version": "v3", "updated": "2013-05-19T14:40:46.000Z" } ], "analyses": { "subjects": [ "43A15" ], "keywords": [ "discrete group", "pompeiu problem", "nonabelian free group", "sufficient condition", "torsion free rank" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1202.2398P" } } }