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05/11/2019, 16:00 — 16:30 — Room P3.31, Mathematics Building

João Esteves, *Instituto Superior Técnico*

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A quantization of the Loday-Ronco Hopf algebra

In previous works we considered a model for topological recursion based on the Hopf Algebra of planar binary trees of Loday and Ronco and showed that extending this Hopf Algebra by identifying pairs of nearest neighbour leaves and thus producing graphs with loops we obtain the full recursion formula of Eynard and Orantin. We also discussed the algebraic structure of the spaces of correlation functions in $g=0$ and in $g\gt 0$. By taking a classical and a quantum product respectively we endowed both spaces with a ring structure. Here we will show that the extended algebra of graphs is in fact a Hopf algebra and can be seen as a sort of quantization of the Loday-Ronco Hopf algebra. This is work in progress.

Part of the Higher Structures and Applications mini-meeting, 5-6 Nov. 2019.