English

Bending Teichm\"uller spaces and character varieties

Geometric Topology 2026-05-19 v6 Complex Variables

Abstract

We consider the mapping bL ⁣:Tχb_L\colon\mathcal{T} \to \chi from the Fricke-Teichm\"uller space T\mathcal{T} into the PSL2C\mathrm{PSL}_2\mathbb{C}-character variety χ\chi of the surface, obtained by bending Fuchsian representations along a fixed measured lamination LL. We prove that this mapping is an equivariant symplectic real-analytic embedding, and, for almost all measured laminations, proper. We also show that this ``bending map'' bL ⁣:Tχb_L\colon \mathcal{T} \to \chi extends continuously almost-everywhere to the canonical inclusion map from the Thurston boundary of T\mathcal{T} into the Morgan-Shalen boundary of χ\chi. Moreover, we ``complexify" this bending map in a geometric manner. Namely, we symplectically embed this real-analytic subvariety ImbL{\rm Im} b_L into the product variety χ×χ\chi \times \chi by the diagonal mapping twisted by complex conjugation. Then we construct a closed C\mathbb{C}-symplectic complex-analytic subvariety of χ×χ\chi \times \chi containing ImbL\mathrm{Im} b_L as a half-dimensional real-analytic subvariety.

Keywords

Cite

@article{arxiv.2203.15394,
  title  = {Bending Teichm\"uller spaces and character varieties},
  author = {Shinpei Baba},
  journal= {arXiv preprint arXiv:2203.15394},
  year   = {2026}
}

Comments

53 pages, 11 figures

R2 v1 2026-06-24T10:29:47.834Z