Consider the hyperbolic space, $\mathbb H^2$. A Fuchsian group is a discrete subgroup of $\text{SL}(2,\mathbb R)$$\text{PSL}(2,\mathbb R)$. We can generate tessellations, especially $\{p,q\} \;\text{tesellations}$ of $\mathbb H^2$ by under the action of a co-compact Fuchsian group. If $p=q=4g$ for $g \geq 2$, then the Fuchsian group can be taken to be the surface group, $\Sigma_g$. I'm interested in tessellations generated by co-comact Fuchsian groups, $\Gamma$. The problem from condensed matter physics I'm thinking about mathematically necessitates the study of character varieties $$C_{\Gamma,n}=\text{Hom}_{\text{Irr}}(\Gamma,\operatorname{SU}(n))$$
Most information I have come across is for the special case where $\Gamma = \Sigma_g$. For instance, the discussion after equation (1.1) in this paper states $C_{\Gamma,n}$ is a smooth manifold. Naturally, I have the following questions:
- What is known about the geometry of $C_{\Gamma,n}$ when $\Gamma$ is not a surface group? Is it a smooth manifold? Complex algebraic variety? Scheme?
- This paper linked above works with integrating functions on $C_{\Gamma,n}$ using the Atiyah-Bott-Goldman measure. Is there an analog of it for a co-compact Fuchsian group?
- Can anything be said under more assumptions on $\Gamma$?
The problem I am working on necessitates the study of $C_{\Gamma,n}$ when $\Gamma$ is a co-compact Fuchsian group. If there are no general answers to the above questions, can we make any "perturbative" argument in the case near $\Gamma$ is a "near-surface group." For instance, only one of the generators might be a elliptic element.
