Nominal String Diagrams

Samuel Balco; Alexander Kurz

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arXiv · 1904.07534

Nominal String Diagrams

Samuel Balco·Alexander Kurz

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Abstract

We introduce nominal string diagrams as, string diagrams internal in the category of nominal sets. This requires us to take nominal sets as a monoidal category, not with the cartesian product, but with the separated product. To this end, we develop the beginnings of a theory of monoidal categories internal in a symmetric monoidal category. As an instance, we obtain a notion of a nominal PROP as a PROP internal in nominal sets. A 2-dimensional calculus of simultaneous substitutions is an application.

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Samuel Balco, Alexander Kurz. 2019-04-16. Nominal String Diagrams. https://arxiv.org/abs/1904.07534

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