You Wouldn't Permutahedron
Abstract
We develop formulas that define permutahedral commutation coherence relations of all orders. To illustrate the result geometrically, we begin by defining a rigid transformation of the -permutahedron into a -cube of dimensions . With a fictitious assumption, we 'define' the corresponding coherence relations 'up to associativity' as an instance of a semi-simplicial type in the language of Displayed Type Theory. This is not a formal result in type theory, but we expect this to translate into one as soon as the problem of defining associahedral coherences is solved in a type theory with semi-simplicial types. On the other hand, this not-strictly-well-typed definition may be used to produce well-typed formulas in a restricted setting.
Cite
@article{arxiv.2407.10891,
title = {You Wouldn't Permutahedron},
author = {Astra Kolomatskaia},
journal= {arXiv preprint arXiv:2407.10891},
year = {2024}
}
Comments
20 pages, 1 figure, v2: new appendix on the theory and implementation of dTT