Patterns of Geodesics, Shearing, and Anosov Representations of the Modular Group
Abstract
Let . Let be the space of discrete faithful representations of the modular group into which map the order generator to an isometry with a unique fixed point. I prove many things about the component of known as the Barbot component: It is homeomorphic to . The boundary parametrizes the Pappus representations from [{\bf S0\/}]. The interior parametrizes the complete extension of the family of Anosov representations from [{\bf BLV\/}]. The members of are isometry groups of embedded patterns of geodesics in which have asymptotic properties like the edges of the Farey triangulation or shears thereof. The Anosov representations are obtained from the Pappus representations by either of two shearing operations in . The shearing structure is encoded by two proper foliations of into rays.
Cite
@article{arxiv.2412.18457,
title = {Patterns of Geodesics, Shearing, and Anosov Representations of the Modular Group},
author = {Richard Evan Schwartz},
journal= {arXiv preprint arXiv:2412.18457},
year = {2026}
}
Comments
This is a shorter version of the paper. In this version, I remove the material about morphed marked boxes and Anosov representations (Chapter 7 and some of Chapter 6). I made a new, self-contained material having that material. I made these changes to make all this work more modular and accessible. Otherwise the paper is the same