BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//talks.cam.ac.uk//v3//EN
BEGIN:VTIMEZONE
TZID:Europe/London
BEGIN:DAYLIGHT
TZOFFSETFROM:+0000
TZOFFSETTO:+0100
TZNAME:BST
DTSTART:19700329T010000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1SU
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:+0100
TZOFFSETTO:+0000
TZNAME:GMT
DTSTART:19701025T020000
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
CATEGORIES:Trinity Mathematical Society
SUMMARY:The Sylvester-Gallai Theorem - Prof. Ben Green (DP
MMS)
DTSTART;TZID=Europe/London:20121112T203000
DTEND;TZID=Europe/London:20121112T213000
UID:TALK40313AThttp://talks.cam.ac.uk
URL:http://talks.cam.ac.uk/talk/index/40313
DESCRIPTION:The Sylvester-Gallai Theorem states that\, given a
ny set P of n points in the plane\, not all on one
line\, there is a line passing through precisely
two of them (and "ordinary line"). I will discuss
the history of this theorem and a couple of proofs
of it. After that I will hint at some more recent
work which establishes that there must in fact be
at least n/2 ordinary lines for all sufficiently
large enough n. I'll also discuss some examples of
sets with few ordinary lines\, which involve some
quite interesting constructions involving ellipti
c curves. The talk will be accessible to Part IA s
tudents.
LOCATION:Winstanley Lecture Theatre\, Trinity College
CONTACT:Mary Fortune
END:VEVENT
END:VCALENDAR