English

On Einstein Structures for $\mathrm{SO}_0(p,p+1)$-Surface Group Representations

Geometric Topology 2026-02-20 v2 Differential Geometry

Abstract

Let SS be a closed surface of genus g2g \geq 2. We study the cocompact domain of discontinuity Ωρ\Omega_{\rho} in the Einstein universe Einp1,p\mathrm{Ein}^{p-1,p} defined by Guichard-Wienhard and Kapovich-Leeb-Porti for a class of pp-Anosov representations ρ:π1SSO0(p,p+1)\rho:\pi_1S \rightarrow \mathrm{SO}_0(p,p+1) including Hitchin representations, for p3p \geq 3. The quotient Mρ=ρ(π1S)\ΩρM_{\rho} = \rho(\pi_1S)\backslash \Omega_{\rho} is abstractly known to be realizable as a fiber bundle over SS, with unknown fiber of unique homotopy type FρF_{\rho}. We explicitly exhibit MρM_{\rho} as a smooth Fρ\mathfrak{F}_{\rho}-fiber bundle over SS, determining the diffeomorphism type of MρM_{\rho} and the unique homotopy type FρF_{\rho}. Surprisingly, in many situations the fiber bundle FρMρS\mathfrak{F}_{\rho} \rightarrow M_{\rho}\rightarrow S is trivial.

Keywords

Cite

@article{arxiv.2510.12779,
  title  = {On Einstein Structures for $\mathrm{SO}_0(p,p+1)$-Surface Group Representations},
  author = {Colin Davalo and Parker Evans},
  journal= {arXiv preprint arXiv:2510.12779},
  year   = {2026}
}

Comments

Substantial changes from v1, including title change. We now address the global topology for all iota-Fuchsian deformations. 35 pages, 4 figures, 1 table

R2 v1 2026-07-01T06:37:13.054Z