BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Louis Esperet (Grenoble) DTSTART:20210305T133000Z DTEND:20210305T143000Z DTSTAMP:20260423T003302Z UID:WCS/21 DESCRIPTION:Title: Asy mptotic dimension of graphs\nby Louis Esperet (Grenoble) as part of Wa rwick Combinatorics Seminar\n\n\nAbstract\nThe asymptotic dimension of a m etric space is a notion introduced by Gromov in the 90s\, in connection wi th geometric group theory. In the special case of the shortest path metric associated to a graph\, a related notion\, called "weak network decomposi tion" has been independently considered by theoretical computer scientists \, with a different motivation. I will also explain some links with the cl assical notion of graph coloring\, and some variants that have been studie d since the end of the 90s.\n\nA class of graphs is minor-closed if any gr aph obtained from a graph in the class by deleting vertices or edges\, or contracting edges\, is still in the class. A typical example is the class of all graphs embeddable on a fixed surface. We prove that every proper mi nor-closed family of graphs has asymptotic dimension at most 2\, which giv es optimal answers to a question of Fujiwara and Papasoglu and to a proble m raised by Ostrovskii and Rosenthal on minor excluded groups.\n\nJoint wo rk with M. Bonamy\, N. Bousquet\, C. Groenland\, C.-H. Liu\, F. Pirot\, an d A. Scott.\n LOCATION:https://researchseminars.org/talk/WCS/21/ END:VEVENT END:VCALENDAR