Blowing up sequences of constant mean curvature tori in $\mathbb{R}^3$ to minimal surfaces
Emma Carberry, Sebastian Klein, Martin Ulrich Schmidt
TL;DR
This work investigates whether blow-ups of solutions to one integrable system can yield solutions to a different integrable system, focusing on sequences of cmc tori in $\mathbb{R}^3$ with unbounded principal curvatures. By blowing up both the domain and ambient space, the sinh-Gordon-based data are transformed into Liouville’s equation in the limit, producing a minimal-surface immersion, with the algebraic-geometric Pinkall–Sterling/Hitchin correspondence carried through to the limit. A main result provides explicit conditions under which the blown-up spectral data converge to a Liouville-type (and hence minimal) limit, with helicoid as a canonical example; the analysis relies on Symes’ method, Iwasawa/Birkhoff decompositions, and a gauge transformation linking Liouville to KdV structures. Overall, the paper establishes a rigorous bridge between cmc geometry and minimal-surface theory via spectral curves and polynomial Killing fields, illuminating how KdV/Liouville integrable systems arise in blow-up limits.
Abstract
This paper is motivated by the question of whether a sequence of solutions of a given integrable system can be blown up to obtain a solution of a different integrable system in the limit. We study a specific example of this phenomenon. Namely, we describe a blow-up for immersed constant mean curvature (cmc) planes of finite type with unbounded principal curvatures and derive sufficient conditions under which this blow-up converges to a minimal surface immersion. Passing to the respective Gauss-Codazzi equations, we are blowing up a sequence of solutions to the sinh-Gordon integrable system to obtain a solution to Liouville's equation, whose integrable system will turn out to be closely related to the Korteweg-de Vries integrable system. Our most important tool for this investigation is the algebraic-geometric correspondence that was established by Pinkall/Sterling and by Hitchin for cmc planes of finite type, which include all cmc tori.
