English

On Lie bialgebras of loops on orientable surface

Geometric Topology 2007-05-23 v1

Abstract

Goldman (Invent. Math. 85(2) (1986) 263) and Turaev (Ann. Sci. Ecole Norm. Sup. (4) 24 (6)(1991) 635) found a Lie bialgebra structure on the vector space generated by non-trivial free homotopy classes of loops on an orientable surface. Chas (Combinatorial Lie bialgebras of curves on surfaces, Topology 43 (2004) 543), by the aid of the computer, found a negative answer to Turaev's question about the characterization of multiples of simple classes in terms of the cobracket, in every surface of negative Euler characteristic and positive genus. However, she left open Turaev's conjecture, namely if, for genus zero, every class with cobracket zero is a multiple of a simple class. The aim of this paper is to give a positive answer to this conjecture.

Keywords

Cite

@article{arxiv.math/0510659,
  title  = {On Lie bialgebras of loops on orientable surface},
  author = {Attilio Le Donne},
  journal= {arXiv preprint arXiv:math/0510659},
  year   = {2007}
}

Comments

9 pages

R2 v1 2026-07-22T17:26:40.615Z