Corrugation Process and ϵ-Isometric Maps

Abstract

Convex Integration is a theory developed in the '70s by M. Gromov. This theory allows to solve families of differential problems satisfying some convex assumptions. From a subsolution, the theory iteratively builds a solution by applying a series of convex integrations. In a previous paper arXiv:1909.04908, we proposed to replace the usual convex integration formula by a new one called Corrugation Process. This new formula is of particular interest when the differential problem under consideration has the property of being of Kuiper. In this paper, we consider the differential problem of $\epsilon$-isometric maps and we prove that it is Kuiper in codimension 1. As an application, we construct $\epsilon$-isometric maps from a short map having a conical singularity.