English

Topology of the space of $d$-pleated surfaces

Geometric Topology 2025-08-08 v1

Abstract

Given a maximal geodesic lamination λ\lambda on a closed oriented surface SS of genus gg, the space of dd-pleated surfaces with pleating locus λ\lambda is an open subset of Hom(π1(S),PGLd(C))\mathrm{Hom}(\pi_1(S),\mathsf{PGL}_d(\mathbb{C})) obtained by applying generalized bending along λ\lambda to Hitchin representations. When d=2d=2, one recovers abstract pleated surfaces in H3\mathbb{H}^3. In this paper, we study the topology of the space R(λ,d)\mathfrak{R}(\lambda,d) of conjugacy classes of dd-pleated surfaces with pleating locus λ\lambda. Firstly, we prove that R(λ,d)\mathfrak{R}(\lambda,d) is real-analytically diffeomorphic to R(d21)(2g2)×(R/2πZ)(d21)(2g2)×Zd\mathbb{R}^{(d^2-1)(2g-2)}\times(\mathbb{R}/2\pi\mathbb{Z})^{(d^2-1)(2g-2)}\times \mathbb{Z}_d, where Zd\mathbb{Z}_d denotes the finite cyclic group of order dd. Furthermore, we show that each connected component of the space of conjugacy classes in Hom(π1(S),PGLd(C))\mathrm{Hom}(\pi_1(S),\mathsf{PGL}_d(\mathbb{C})) contains exactly one component of R(λ,d)\mathfrak{R}(\lambda,d).

Keywords

Cite

@article{arxiv.2508.04813,
  title  = {Topology of the space of $d$-pleated surfaces},
  author = {Sara Maloni and Giuseppe Martone and Filippo Mazzoli and Tengren Zhang},
  journal= {arXiv preprint arXiv:2508.04813},
  year   = {2025}
}

Comments

69 pages, 17 figures. Comments are welcome!