Beyond Almost Fuchsian Space

abstract: An almost Fuchsian manifold is a hyperbolic three-manifold of the type $S\times\R$ which admits a closed minimal surface (homotopic to $S\times\{0\}$) with the maximum principal curvature $\lambda_0<1$, while a weakly almost Fuchsian manifold is of the same type but it admits a closed minimal surface with $\lambda_0 \le1$. We first prove that any weakly almost Fuchsian manifold is geometrically finite, and we construct a Canary-Storm type compactification for the weakly almost Fuchsian space. We use this to prove uniform upper bounds on the volume of the convex core and Hausdorff dimension of the limit sets of weakly almost Fuchsian manifolds, and to prove a gap theorem for the principal curvatures of minimal surfaces in hyperbolic 3-manifolds that fiber over the circle. We also give examples of quasi-Fuchsian manifolds which admit unique closed minimal surfaces without being weakly almost Fuchsian.