BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//UM//UM*Events//EN
CALSCALE:GREGORIAN
BEGIN:VTIMEZONE
TZID:America/Detroit
TZURL:http://tzurl.org/zoneinfo/America/Detroit
X-LIC-LOCATION:America/Detroit
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20070311T020000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20071104T020000
RRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTAMP:20240816T104339
DTSTART;TZID=America/Detroit:20240822T150000
DTEND;TZID=America/Detroit:20240822T160000
SUMMARY:Workshop / Seminar:An equator theorem for the 2-sphere
DESCRIPTION:We will focus on the group of Hamiltonian diffeomorphisms (and/or area-preserving homeomorphisms) of the 2-sphere. A tremendous amount of progress has been made in the study of these groups in the last few years\, but many problems remain\, including the Equator Conjecture. An equator on the 2-sphere is a simple closed curve whose complementary components have equal area. The Equator Conjecture predicts that for any positive K\, there are pairs of equators such that any Hamiltonian diffeomorphism sending one equator to the other must have Hofer norm larger than K. We will prove an alternative conjecture\, where we replace “Hofer norm” with “quantitative fragmentation norm”. To prove this\, we construct new quasimorphisms defined on the group of area-preserving homeomorphisms of the 2-sphere\, coming from methods inspired from mapping class groups and geometric group theory. Joint work with Yongsheng Jia.
UID:124345-21852922@events.umich.edu
URL:https://events.umich.edu/event/124345
CLASS:PUBLIC
STATUS:CONFIRMED
CATEGORIES:Mathematics
LOCATION:East Hall - 3866
CONTACT:
END:VEVENT
END:VCALENDAR