English
Related papers

Related papers: Almost-fuchsian structures on disk bundles over a …

200 papers

A Fuchsian group $\Gamma$ has a modular embedding if its adjoint trace field is a totally real number field and every unbounded Galois conjugate $\Gamma^\sigma$ comes equipped with a holomorphic (or conjugate holomorphic) map ${\phi^\sigma…

Geometric Topology · Mathematics 2026-01-14 Matthew Stover

We prove that any nonabelian, non-Fuchsian representation of a surface group into PSL(2,R) is the holonomy of a folded hyperbolic structure on the surface. Using similar ideas, we establish that any non-Fuchsian representation rho of a…

Geometric Topology · Mathematics 2016-01-20 François Guéritaud , Fanny Kassel , Maxime Wolff

For a $2n+1$-dimensional compact Sasakian manifold, if $n\ge 2$, we prove that the analytic germ of the variety of representations of the fundamental group at every semi-simple representation is quadratic. To prove this result, we prove the…

Differential Geometry · Mathematics 2020-07-30 Hisashi Kasuya

Let $M =\mathbb{H}^3/\Gamma$ be a finite-volume, noncompact hyperbolic 3-manifold. We show that the number of quasi-Fuchsian surface subgroups of $\Gamma$ (up to conjugacy and commensurability) of genus at most $g$ is bounded both above and…

Geometric Topology · Mathematics 2026-03-06 Xiaolong Hans Han , Zhenghao Rao , Jia Wan

Bolibruch's examples of representations of pi_1(P^1-finitely many points) which are not realizable by Fuchsian differential systems are adapted to curves of higher genus.

Algebraic Geometry · Mathematics 2007-05-23 Hélène Esnault , Claus Hertling

This paper concerns with deformations of noncompact complex hyperbolic manifolds (with locally Bergman metric), varieties of discrete representations of their fundamental groups into $PU(n,1)$ and the problem of (quasiconformal) stability…

Differential Geometry · Mathematics 2009-09-25 Boris Apanasov

We prove the representation given by a stable $\alpha_1$-cyclic parabolic $\mathrm{SO}_0(2,3)$-Higgs bundle through the non-Abelian Hodge correspondence is $\{\alpha_2\}$-almost dominated. This is a generalization of Filip's result on…

Differential Geometry · Mathematics 2025-08-22 Junming Zhang

Recall that the group $PSL(2,\mathbb R)$ is isomorphic to $PSp(2,\mathbb R),\ SO_0(1,2)$ and $PU(1,1).$ The goal of this paper is to examine the various ways in which Fuchsian representations of the fundamental group of a closed surface of…

Differential Geometry · Mathematics 2017-04-11 Brian Collier

We study the subgroup structure, Hecke algebras, quasi-regular representations, and asymptotic properties of some fractal groups of branch type. We introduce parabolic subgroups, show that they are weakly maximal, and that the corresponding…

Group Theory · Mathematics 2009-11-27 Laurent Bartholdi , Rostislav I. Grigorchuk

We give a geometric interpretation of Fock--Goncharov positivity and show that bending deformations of Fuchsian representations stabilize a uniform Finsler quasi-convex disk in the symmetric space $\mathrm{PSL}_d(\mathbb…

Differential Geometry · Mathematics 2025-07-03 Pierre-Louis Blayac , Ursula Hamenstädt , Théo Marty

This is a survey article whose main goal is to explain how many components of the character variety of a closed surface are either deformation spaces of representations into the maximal compact subgroup or deformation spaces of certain…

Algebraic Geometry · Mathematics 2019-02-13 Brian Collier

We introduce the concept of a Fock bundle, a smooth principal bundle over a surface equipped with a special kind of adjoint-valued 1-form, as a new tool for studying character varieties of surface groups. Although similar to Higgs bundles,…

Differential Geometry · Mathematics 2023-12-13 Georgios Kydonakis , Charlie Reid , Alexander Thomas

This paper gives a construction for all minimal immersions $f$ of the Poincar\'{e} disc into the complex hyperbolic plane $\mathbb{CH}^2$ which are equivariant with respect to an irreducible representation $\rho$ of a hyperbolic surface…

Differential Geometry · Mathematics 2020-09-08 John Loftin , Ian McIntosh

Let Gamma < PSL_2(C) be discrete, cofinite volume, and noncocompact. We prove that for all K > 1, there is a subgroup H < Gamma that is K-quasiconformally conjugate to a discrete cocompact subgroup of PSL_2(R). Along with previous work of…

Geometric Topology · Mathematics 2023-02-22 Jeremy Kahn , Alex Wright

Using the $L^2$ norm of the Higgs field as a Morse function, we study the moduli spaces of $U(p,q)$-Higgs bundles over a Riemann surface. We require that the genus of the surface be at least two, but place no constraints on $(p,q)$. A key…

Algebraic Geometry · Mathematics 2007-05-23 Steven B. Bradlow , Oscar Garcia-Prada , Peter B. Gothen

We study limits of quasifuchsian groups for which the bending measures on the convex hull boundary tend to zero, giving necessary and sufficient conditions for the limit group to exist and be Fuchsian. As an application we complete the…

Geometric Topology · Mathematics 2007-05-23 C. Series

Let $M$ be a closed hyperbolic $3$-manifold. A homotopy class $[S]$ of surfaces in $M$ is filling if any representative cuts $M$ into components contractible in $M$. We prove that there exist $\epsilon_0, g_0>0$ such that every homotopy…

Geometric Topology · Mathematics 2026-03-20 Xiaolong Hans Han

Approximate algebraic structures play a defining role in arithmetic combinatorics and have found remarkable applications to basic questions in number theory and pseudorandomness. Here we study approximate representations of finite groups:…

Representation Theory · Mathematics 2010-10-01 Cristopher Moore , Alexander Russell

On the group $\rm{Symp}(D, \partial D)$ of symplectomorphisms of the disk which are the identity near the boundary, there are homogeneous quasi-morphisms called the Ruelle invariant and Gambaudo-Ghys quasi-morphisms. In this paper, we show…

Geometric Topology · Mathematics 2020-05-22 Shuhei Maruyama

Using the L^2 norm of the Higgs field as a Morse function, we study the moduli spaces of U(p,q)-Higgs bundles over a Riemann surface. We require that the genus of the surface be at least two, but place no constraints on (p,q). A key step is…

Algebraic Geometry · Mathematics 2022-11-15 Steven B. Bradlow , Oscar Garcia-Prada , Peter B. Gothen