{ "id": "1404.7019", "version": "v1", "published": "2014-04-28T15:24:02.000Z", "updated": "2014-04-28T15:24:02.000Z", "title": "Typical curvature behaviour of bodies of constant width", "authors": [ "Imre Barany", "rolf Schneider" ], "categories": [ "math.MG" ], "abstract": "It is known that an $n$-dimensional convex body which is typical in the sense of Baire category, shows a simple, but highly non-intuitive curvature behaviour: at almost all of its boundary points, in the sense of measure, all curvatures are zero, but there is also a dense and uncountable set of boundary points at which all curvatures are infinite. The purpose of this paper is to find a counterpart to this phenomenon for typical convex bodies of given constant width. Such bodies cannot have zero curvatures. A main result says that for a typical $n$-dimensional convex body of constant width $1$ (without loss of generality), at almost all boundary points, in the sense of measure, all curvatures are equal to $1$. (In contrast, note that a ball of width $1$ has radius $1/2$, hence all its curvatures are equal to $2$.) Since the property of constant width is linear with respect to Minkowski addition, the proof requires recourse to a linear curvature notion, which is provided by the tangential radii of curvature.", "revisions": [ { "version": "v1", "updated": "2014-04-28T15:24:02.000Z" } ], "analyses": { "subjects": [ "52A20", "53A07" ], "keywords": [ "constant width", "typical curvature behaviour", "boundary points", "dimensional convex body", "linear curvature notion" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1404.7019B" } } }