English

The geometry of the space of branched Rough Paths

Probability 2020-03-20 v5

Abstract

We construct an explicit transitive free action of a Banach space of H\"older functions on the space of branched rough paths, which yields in particular a bijection between theses two spaces. This endows the space of branched rough paths with the structure of a principal homogeneous space over a Banach space and allows to characterize its automorphisms. The construction is based on the Baker-Campbell-Hausdorff formula, on a constructive version of the Lyons-Victoir extension theorem and on the Hairer-Kelly map, which allows to describe branched rough paths in terms of anisotropic geometric rough paths.

Keywords

Cite

@article{arxiv.1810.12179,
  title  = {The geometry of the space of branched Rough Paths},
  author = {Nikolas Tapia and Lorenzo Zambotti},
  journal= {arXiv preprint arXiv:1810.12179},
  year   = {2020}
}

Comments

Final version to appear in Proceedings of the London Mathematical Society. 34 pages