Bending parameterization of one-sided degenerated Kleinian surface groups
Bruno Dular
TL;DR
We address the problem of extending bending-parameterization rigidity to one-sided degenerations of Kleinian surface groups. The main result shows that for one-sided degenerated structures $\rho\in{\mathcal AH}_o^+(S;e^-)$, the manifold is uniquely determined by the end structure $\mathrm E^-(\rho)$ and the top bending lamination $\mathrm b^+(\rho)$, i.e. by the pair $(m^-(\rho), b^+(\rho))$ up to the specified end data. The authors prove this by establishing continuity, properness, and injectivity of the map $\mathrm m^-\\times\\mathrm b^+$ from ${\mathcal AH}_o^+(S;e^-)$ to $\mathcal T(\Sigma^-)\\times{\mathcal ML}^{\perp e^-}_{<\pi}(S^+)$, leveraging the ending lamination theorem, Thurston’s grafting parameterization, and Morgan–Shalen limits. Consequently, the work extends the bending-parameterization paradigm from quasi-Fuchsian to a broad class of degenerations and clarifies how end invariants control the geometry of the convex core and conformal boundary.
Abstract
It was recently proved that quasi-Fuchsian manifolds are uniquely determined by their bending laminations. This paper concerns a similar result for certain non-quasi-Fuchsian manifolds~: those obtained by degenerating one end but not the other, i.e. those appearing in boundaries of Bers slices. More precisely, we show that such hyperbolic manifolds are uniquely determined by the end structure of the degenerated end and the bending lamination of the other. The end structure consists of the parabolic locus, which is a multicurve, together with ending laminations or conformal structures on each components of its complement.
