Functions on a swallowtail

Abstract

We classify submersions from $({\mathbb{R}}^3,0)$ to $(\mathbb{R},0)$ up to diffeomorphisms which preserve the swallowtail and use this classification to study its flat geometry. The flat geometry is derived from the contact of the swallowtail with planes, which is measured by the singularities of the height function.

13 pages, 4 figures