On Associators and the Grothendieck-Teichmuller Group I

Dror Bar-Natan

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On Associators and the Grothendieck-Teichmuller Group I

Dror Bar-Natan

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Abstract

We present a formalism within which the relationship (discovered by Drinfel'd) between associators (for quasi-triangular quasi-Hopf algebras) and (a variant of) the Grothendieck-Teichmuller group becomes simple and natural, leading to a simplification of Drinfel'd's original work. In particular, we re-prove that rational associators exist and can be constructed iteratively, though the proof itself still depends on the apriori knowledge that a not-necessarily-rational associator exists.

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BibTeX RIS

Dror Bar-Natan. 1999-06-03. On Associators and the Grothendieck-Teichmuller Group I. https://arxiv.org/abs/q-alg/9606021

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