On the Inheritance of Orbifold Substructures

TL;DR

This paper explores how orbifold substructures are inherited through a chain of orbifolds, revealing complexities and limitations in canonical inheritance and the role of saturation.

Contribution

It provides a detailed analysis of orbifold structure inheritance, introduces examples illustrating when inheritance is canonical or fails, and examines the concept of saturation in suborbifolds.

Findings

Canonical inheritance can fail in intermediate orbifolds.

When suborbifolds are embedded, canonical structures agree.

Saturation is a key property influencing inheritance.

Abstract

In a previous article, we defined a very flexible notion of suborbifold and characterized those suborbifolds which can arise as the images of orbifold embeddings. In particular, suborbifolds are images of orbifold embeddings precisely when they are saturated and split. This article addresses the problem of orbifold structure inheritance for three orbifolds $\mathcal{Q}\subset\mathcal{P}\subset\mathcal{O}$. We identify an appealing but ultimately inadequate notion of an inherited canonical orbifold substructure. In particular, we give a concrete example where the orbifold structure of $\mathcal{Q}$ is canonically inherited from $\mathcal{P}$, and the orbifold structure of $\mathcal{P}$ is canonically inherited from $\mathcal{O}$, but the orbifold structure of $\mathcal{Q}$ is not canonically inherited from $\mathcal{O}$. On the other hand, it is easy to see that when $\mathcal{Q}$ is embedded in $\mathcal{P}$, and $\mathcal{P}$ is embedded in $\mathcal{O}$, all of the canonical inherited orbifold substructures will agree. We also investigate the property of saturation in this context, and give an example of a suborbifold with the canonical orbifold substructure that is not saturated.