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SUMMARY:The Hopf algebra of dissection polylogarithms - Dupont\, C (Instit
 ut de Mathmatiques de Jussieu)
DTSTART:20130410T093000Z
DTEND:20130410T103000Z
UID:TALK44416@talks.cam.ac.uk
CONTACT:Mustapha Amrani
DESCRIPTION:Grothendieck's theory of motives has given birth to a conjectu
 ral Galois theory for periods. Replacing the periods with their motivic av
 atars\, one gets an algebra of motivic periods that are acted upon by a mo
 tivic Galois group. Recently\, the computation of this action for multiple
  zeta values has been studied and used by Deligne\, Goncharov and Brown am
 ong others. In this talk we will introduce a family of periods indexed by 
 some combinatorial objects called dissection diagrams\, and compute the ac
 tion of the motivic Galois group on their motivic avatars. This generalize
 s the case of (generic) iterated integrals on the punctured complex plane.
  We will show that the motivic action is given by a very simple combinator
 ial Hopf algebra.\n\n
LOCATION:Seminar Room 1\, Newton Institute
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