BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250805T154431EDT-2939DolJU2@132.216.98.100 DTSTAMP:20250805T194431Z DESCRIPTION:On convex normal subgroups.\n\nA subgroup H of a left ordered g roup (G\, $le$) is $le$-convex if for any x\,z $in$ H and y $in$ G the ine qualities x $le$ y $le$ z imply y∈H. I will show that the family of $le$-c onvex normal subgroup can be finite of arbitrary size bigger than 1\, coun tably infinite\, or of cardinality continuum. I will also point out there is no countable universal left-orderable group.\n DTSTART:20180214T200000Z DTEND:20180214T210000Z LOCATION:Room 920\, Burnside Hall\, CA\, QC\, Montreal\, H3A 0B9\, 805 rue Sherbrooke Ouest SUMMARY:Junyu Lu\, 9IÖÆ×÷³§Ãâ·Ñ URL:/mathstat/channels/event/junyu-lu-mcgill-universit y-285065 END:VEVENT END:VCALENDAR