{ "id": "2403.07900", "version": "v1", "published": "2024-02-25T19:44:14.000Z", "updated": "2024-02-25T19:44:14.000Z", "title": "Applications of equidistant supporting surfaces of a convex body in the hyperbolic space", "authors": [ "Marek Lassak" ], "comment": "7 pages. arXiv admin note: text overlap with arXiv:2401.07831", "categories": [ "math.MG" ], "abstract": "For a hyperplane $H$ supporting a convex body $C$ in the hyperbolic space $\\mathbb{H}^d$ we define the width of $C$ determined by $H$ as the distance between $H$ and a most distant ultraparallel hyperplane supporting $C$. The thickness (i.e., the minimum width) of $C$ is denoted by $\\Delta(C)$. A convex body $R \\subset \\mathbb{H}^d$ is called reduced if for every body $Z \\subsetneq R$ we have $\\Delta(Z) < \\Delta(R)$. We show that for any extreme point $e$ of a reduced body $R \\subset \\mathbb{H}^d$ there exists a supporting hyperplane $H$ of $R$ which passes through $e$ or its equidistant surface supporting $R$ passes through $e$. Bodies of constant width in $\\mathbb{H}^d$ are defined as bodies whose all widths are equal. We prove that every complete body in $\\mathbb{H}^d$ is a body of constant width.", "revisions": [ { "version": "v1", "updated": "2024-02-25T19:44:14.000Z" } ], "analyses": { "subjects": [ "52A55" ], "keywords": [ "convex body", "equidistant supporting surfaces", "hyperbolic space", "constant width", "applications" ], "note": { "typesetting": "TeX", "pages": 7, "language": "en", "license": "arXiv", "status": "editable" } } }