A general halfspace theorem for constant mean curvature surfaces

In this paper, we prove a general halfspace theorem for constant mean curvature surfaces. Under certain hypotheses, we prove that, in an ambient space M^3, any constant mean curvature H_0 surface on one side of a constant mean curvature H_0 surface \Sigma_0 is an equidistant surface to \Sigma_0. The main hypotheses of the theorem are that \Sigma_0 is parabolic and the mean curvature of the equidistant surfaces to \Sigma_0 evolves in a certain way.Comment: 3 figures, sign mistakes at the beginning of Section 6 are correcte

The Plateau problem at infinity for horizontal ends and genus 1

In this paper, we study Alexandrov-embedded r-noids with genus 1 and horizontal ends. Such minimal surfaces are of two types and we build several examples of the first one. We prove that if a polygon bounds an immersed polygonal disk, it is the flux polygon of an r-noid with genus 1 of the first type. We also study the case of polygons which are invariant under a rotation. The construction of these surfaces is based on the resolution of the Dirichlet problem for the minimal surface equation on an unbounded domain.Comment: 63 page

On minimal spheres of area 4π4\pi and rigidity

Let $M$ be a complete Riemannian $3$-manifold with sectional curvatures between $0$ and $1$. A minimal $2$-sphere immersed in $M$ has area at least $4\pi$. If an embedded minimal sphere has area $4\pi$, then $M$ is isometric to the unit $3$-sphere or to a quotient of the product of the unit $2$-sphere with $\mathbb{R}$, with the product metric. We also obtain a rigidity theorem for the existence of hyperbolic cusps. Let $M$ be a complete Riemannian $3$-manifold with sectional curvatures bounded above by $-1$. Suppose there is a $2$-torus $T$ embedded in $M$ with mean curvature one. Then the mean convex component of $M$ bounded by $T$ is a hyperbolic cusp;,i.e., it is isometric to $T \times \mathbb{R}$ with the constant curvature $-1$ metric: $e^{-2t}d\sigma_0^2+dt^2$ with $d\sigma_0^2$ a flat metric on $T$.Comment: 8 page

Minimal surfaces near short geodesics in hyperbolic 33-manifolds

If $M$ is a finite volume complete hyperbolic $3$-manifold, the quantity $\mathcal A_1(M)$ is defined as the infimum of the areas of closed minimal surfaces in $M$. In this paper we study the continuity property of the functional $\mathcal A_1$ with respect to the geometric convergence of hyperbolic manifolds. We prove that it is lower semi-continuous and even continuous if $\mathcal A_1(M)$ is realized by a minimal surface satisfying some hypotheses. Understanding the interaction between minimal surfaces and short geodesics in $M$ is the main theme of this paperComment: 35 pages, 4 figure