Lusin Approximation and Horizontal Curves in Carnot Groups
Metric Geometry
2015-11-26 v4
Abstract
We show that, given an absolutely continuous horizontal curve in the Heisenberg group, there is a horizontal curve such that and outside a set of small measure. Conversely, we construct an absolutely continuous horizontal curve in the Engel group with no horizontal approximation.
Cite
@article{arxiv.1412.2531,
title = {Lusin Approximation and Horizontal Curves in Carnot Groups},
author = {Gareth Speight},
journal= {arXiv preprint arXiv:1412.2531},
year = {2015}
}
Comments
21 pages. Corrected a technical error in the argument for the Heisenberg group and added previously omitted proofs. Improved the exposition and corrected typos as suggested by referees. To appear in Revista Matematica Iberoamericana