Elliptic associators

Autor: Enriquez, B.
Rok vydání: 2010
Předmět:
Druh dokumentu: Working Paper
Popis: We construct a genus one analogue of the theory of associators and the Grothendieck-Teichmueller group. The analogue of the Galois action on the profinite braid groups is an action of the arithmetic fundamental group of a moduli space of elliptic curves on the profinite braid groups in genus one. This action factors through an explicit profinite group hat GT_ell, which admits an interpretation in terms of decorations of braided monoidal categories. We relate this group to its prounipotent group scheme version GT_ell(-). We construct a torsor over the latter group, the scheme of elliptic associators. An explicit family of elliptic associators is constructed, based on our earlier work with Calaque and Etingof on the universal KZB connexion. The existence of elliptic associators enables one to show that the Lie algebra of GT_ell(-) is isomorphic to a graded Lie algebra, on which we obtain several results: semidirect product structure; explicit generators. This existence also allows one to compute the Zariski closure of the mapping class group in genus one (isomorphic to the braid group B_3) in the automorphism groups of the prounipotent completions of braid groups in genus one. The analytic study of the family of elliptic associators produces relations between MZVs and iterated integrals of Eisenstein series.
Comment: 67 pages. The exposition has been reorganized. The Lie algebra grt_ell introduced in the paper is compared to a similar Lie algebra introduced by Tsunogai. The results of the section on iterated integrals of Eisenstein series have been made more precise: some iterated integrals are computed explicitly in terms of MZVs
Databáze: arXiv