The geometry of the space of branched rough paths
In this talk we wish to discuss several constructions related to branched rough paths (BRPs), a notion which has been introduced by M. Gubinelli and later generalised by M. Hairer in the theory of regularity structures. We show that one can build a transitive action of a linear space onto BRPs, that this yields a surprising bijection between these two spaces, and that BRPs have the structure of a fiber bundle.