{ "id": "1005.5222", "version": "v1", "published": "2010-05-28T06:22:35.000Z", "updated": "2010-05-28T06:22:35.000Z", "title": "Degenerations and orbits in finite abelian groups", "authors": [ "Kunal Dutta", "Amritanshu Prasad" ], "comment": "14 pages, 5 figures", "journal": "Journal of Combinatorial Theory, Series A, Volume 118, Issue 6, August 2011, Pages 1685-1694", "doi": "10.1016/j.jcta.2011.02.002", "categories": [ "math.GR", "math.CO", "math.NT" ], "abstract": "A notion of degeneration of elements in groups is introduced. It is used to parametrize the orbits in a finite abelian group under its full automorphism group by a finite distributive lattice. A pictorial description of this lattice leads to an intuitive self-contained exposition of some of the basic facts concerning these orbits, including their enumeration. Given a partition $\\lambda$, the lattice parametrizing orbits in a finite abelian p-group of type $\\lambda$ is found to be independent of p. The order of the orbit corresponding to each parameter, which turns out to be a polynomial in p, is calculated. The description of orbits is extended to subquotients by certain characteristic subgroups. Each such characteristic subquotient is shown to have a unique maximal orbit.", "revisions": [ { "version": "v1", "updated": "2010-05-28T06:22:35.000Z" } ], "analyses": { "subjects": [ "20K01", "05A15" ], "keywords": [ "finite abelian group", "degeneration", "unique maximal orbit", "full automorphism group", "finite abelian p-group" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 14, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1005.5222D" } } }