{ "id": "1912.06012", "version": "v1", "published": "2019-12-12T15:04:20.000Z", "updated": "2019-12-12T15:04:20.000Z", "title": "The phase transition for parking on Galton--Watson trees", "authors": [ "Nicolas Curien", "Olivier Hénard" ], "comment": "15 pages, 5 figures", "categories": [ "math.PR", "math.CO" ], "abstract": "We establish a phase transition for the parking process on critical Galton--Watson trees. In this model, a random number of cars with mean $m$ and variance $\\sigma^{2}$ arrive independently on the vertices of a critical Galton--Watson tree with finite variance $\\Sigma^{2}$ conditioned to be large. The cars go down the tree and try to park on empty vertices as soon as possible. We show a phase transition depending on $$ \\Theta:= (1-m)^2- \\Sigma^2 (\\sigma^2+m^2-m).$$ Specifically, if $ \\Theta>0,$ then most cars will manage to park, whereas if $\\Theta<0$ then a positive fraction of the cars will not find a spot and exit the tree through the root. This confirms a conjecture of Goldschmidt and Przykucki.", "revisions": [ { "version": "v1", "updated": "2019-12-12T15:04:20.000Z" } ], "analyses": { "subjects": [ "60C05" ], "keywords": [ "phase transition", "critical galton-watson tree", "random number", "finite variance", "empty vertices" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable" } } }