{ "id": "1210.2231", "version": "v3", "published": "2012-10-08T10:58:58.000Z", "updated": "2013-05-06T08:50:11.000Z", "title": "Tail asymptotics of free path lengths for the periodic Lorentz process. On Dettmann's geometric conjectures", "authors": [ "Peter Nandori", "Domokos Szasz", "Tamas Varju" ], "categories": [ "math.DS" ], "abstract": "In the simplest case, consider a $\\mathbb{Z}^d$-periodic ($d \\geq 3$) arrangement of balls of radii < 1/2, and select a random direction and point (outside the balls). According to Dettmann's first conjecture, the probability that the so determined free flight (until the first hitting of a ball) is larger than $t >>1$ is $\\sim \\frac{C}{t}$, where $C$ is explicitly given by the geometry of the model. In its simplest form, Dettmann's second conjecture is related to the previous case with tangent balls (of radii 1/2). The conjectures are established in a more general setup: for $\\mathcal{L}$-periodic configuration of - possibly intersecting - convex bodies with $\\mathcal{L}$ being a non-degenerate lattice. These questions are related to P\\'olya's visibility problem (1918), to theories of Bourgain-Golse-Wennberg (1998-) and of Marklof-Str\\\"{o}mbergsson (2010-). The results also provide the asymptotic covariance of the periodic Lorentz process assuming it has a limit in the super-diffusive scaling, a fact if $d = 2$ and the horizon is infinite.", "revisions": [ { "version": "v3", "updated": "2013-05-06T08:50:11.000Z" } ], "analyses": { "subjects": [ "37D50" ], "keywords": [ "periodic lorentz process", "free path lengths", "dettmanns geometric conjectures", "tail asymptotics", "dettmanns first conjecture" ], "publication": { "doi": "10.1007/s00220-014-2086-x", "journal": "Communications in Mathematical Physics", "year": 2014, "month": "Oct", "volume": 331, "number": 1, "pages": 111 }, "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014CMaPh.331..111N" } } }