{ "id": "1403.5378", "version": "v3", "published": "2014-03-21T06:39:41.000Z", "updated": "2014-08-27T19:25:22.000Z", "title": "Ehrhart series, unimodality, and integrally closed reflexive polytopes", "authors": [ "Benjamin Braun", "Robert Davis" ], "categories": [ "math.CO" ], "abstract": "An interesting open problem in Ehrhart theory is to classify those lattice polytopes having a unimodal $h^*$-vector. Although various sufficient conditions have been found, necessary conditions remain a challenge. In this paper, we consider integrally closed reflexive simplices and discuss an operation that preserves reflexivity, integral closure, and unimodality of the $h^*$-vector, providing one explanation for why unimodality occurs in this setting. We also discuss the failure of proving unimodality in this setting using weak Lefschetz elements.", "revisions": [ { "version": "v2", "updated": "2014-03-25T17:08:55.000Z", "abstract": "An interesting open problem in Ehrhart theory is to classify those lattice polytopes having a unimodal $h^*$-vector. Although various sufficient conditions have been found, necessary conditions remain a challenge. In this paper, we consider integrally closed reflexive polytopes and discuss an operation that preserves reflexivity, integral closure, and unimodality of the $h^*$-vector, providing one explanation for why unimodality occurs in this setting. We also discuss the special case of reflexive simplices.", "comment": null, "journal": null, "doi": null }, { "version": "v3", "updated": "2014-08-27T19:25:22.000Z" } ], "analyses": { "subjects": [ "05A15", "52B20" ], "keywords": [ "integrally closed reflexive polytopes", "ehrhart series", "unimodality", "necessary conditions remain", "ehrhart theory" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1403.5378B" } } }