BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20251123T200304EST-4304p1Bnzt@132.216.98.100 DTSTAMP:20251124T010304Z DESCRIPTION:Title: The Open Graph Dichotomy and the second level of the Bor el hierarchy\n\nAbstract:\n\nI will sketch a game-theoretical proof of the open graph dichotomy for box-open hypergraphs\, and explain how it can be used to obtain various descriptive-set-theoretical dichotomies at the sec ond level of the Borel hierarchy. This shows how to generalise these dicho tomies from analytic metric spaces to separable metric spaces by working u nder the axiom of determinacy.\n If time allows it\, I will also discuss so me connections between cardinal invariants and the chromatic number of the graphs at stake.\n This is joint work with Benjamin D. Miller and Daniel T . Soukup.\n DTSTART:20190219T193000Z DTEND:20190219T203000Z LOCATION:Room 920\, Burnside Hall\, CA\, QC\, Montreal\, H3A 0B9\, 805 rue Sherbrooke Ouest SUMMARY:Raphael Carroy (Vienna) URL:/mathstat/channels/event/raphael-carroy-vienna-294 667 END:VEVENT END:VCALENDAR