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arXiv · 0807.0658

A diagrammatic approach to Hopf monads

Simon Willerton
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Abstract

Given a Hopf algebra in a symmetric monoidal category with duals, the category of modules inherits the structure of a monoidal category with duals. If the notion of algebra is replaced with that of monad on a monoidal category with duals then Bruguieres and Virelizier showed when the category of modules inherits this structure of being monoidal with duals, and this gave rise to what they called a Hopf monad. In this paper it is shown that there are good diagrammatic descriptions of dinatural transformations which allows the three-dimensional, object-free nature of their constructions to become apparent.

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Simon Willerton. 2008-07-03. A diagrammatic approach to Hopf monads. https://arxiv.org/abs/0807.0658

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