What's in a name? Parallel Universes

Abstract

Every compact oriented Riemann surface with a finite group of self homeomorphisms can be embedded conformally in Euclidean three space so that the image group acts conformally. Here we establish necessary and sufficient conditions on the fixed point structure as given by Harvey's surface kernel map for the image group to lift to the three sphere. This builds upon topological work of Ni, Wang and Wang. It gives rise to a discussion of how terms emerge and are used for equivalent phenomena that are described in the language of different fields.