On positive opetopes, positive opetopic cardinals and positive opetopic set

TL;DR

This paper introduces positive opetopes and positive opetopic cardinals as finite combinatorial structures, providing a combinatorial description of positive-to-one polygraphs and establishing their categorical properties.

Contribution

It defines positive opetopes and cardinals, and shows that positive-to-one polygraphs form a presheaf category with a specific exponent category.

Findings

Positive-to-one polygraphs form a presheaf category.

The category of omega-categories is monadic over positive-to-one polygraphs.

Explicit combinatorial description of positive-to-one polygraphs.

Abstract

We introduce the notion of a positive opetope and positive opetopic cardinals as certain finite combinatorial structures. The positive opetopic cardinals to positive-to-one polygraphs are like simple graphs to free omega-categories over omega-graphs, c.f. [MZ]. In particular, they allow us to give an explicit combinatorial description of positive-to-one polygraphs. Using this description we show, among other things, that positive-to-one polygraphs form a presheaf category with the exponent category being the category of positive opetopes. We also show that the category of omega-categories is monadic over the category of positive-to-one polygraphs with the `free functor' being an inclusion.