BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Proof of the zig-zag conjecture - Schnetz\, O (Friedrich-Alexander
 -Universitt Erlangen-Nrnberg)
DTSTART:20130411T123000Z
DTEND:20130411T133000Z
UID:TALK44466@talks.cam.ac.uk
CONTACT:Mustapha Amrani
DESCRIPTION:In quantum field theory primitive Feynman graphs give--via the
  period map--rise to renormalization scheme independent contribution to th
 e beta function. While the periods of many Feynman graphs are multiple zet
 a values there exists the distinguished family of zig-zag graphs whose per
 iods were conjectured in 1995 by Broadhurst and Kreimer to be certain rati
 onal multiples of odd single zetas. \n\nIn joint work with F. Brown it was
  possible in 2012 to prove the zig-zag conjecture using the theory of grap
 hical functions\, single valued multiple polylogarithms and a theorem by D
 . Zagier on multiple zeta values of the form zeta(2\,...\,2\,3\,2\,...\,2)
 .\n
LOCATION:Seminar Room 1\, Newton Institute
END:VEVENT
END:VCALENDAR