Minimal Graph Transformations and their Classification
Sam K Mathew
TL;DR
This work provides a complete classification of minimal graph surfaces that admit graphical transformations into other minimal graphs, distinguishing trivial affine transforms from genuine nontrivial transformations. By formulating the Non-Trivial Minimal Graph Transformation Equations and introducing the First and Second Characteristic Functions, the authors reduce the problem to a weakened complex-ODE for a holomorphic function, which they solve case-by-case using complex analysis and elliptic function theory. The analysis yields explicit families of minimal surfaces—ranging from Scherk’s surfaces to catenoids and novel elliptic-function–based surfaces (Pillars, Great/Thick/Sharp Walls)—with precise transformations mapping between members of each family. Domain considerations, singular-point analyses, and analytic continuation ensure well-defined transformations, while appendices provide the analytic and elliptic-function tools required. The results extend classical minimal-surface transformations (e.g., Bäcklund/Ribaucour-type ideas) with a rigorous, complete classification and reveal several previously unknown minimal surface families. These findings have potential implications for generating new minimal surfaces with shared contour lines and for further explorations of maximal/minimal graph transformation dualities.
Abstract
This paper presents a complete classification of minimal graph surfaces that admit graphical transformations into other minimal surfaces. These transformations are functions that map the height function of a minimal graph surface to another height function, which also describes a minimal graph surface. While trivial maps such as translations and reflections exist, we formulate and solve the Non-Trivial Minimal Graph Transformation Problem, governed by a coupled system of partial differential equations. A central result establishes the rigorous equivalence of this original system to a modified problem for a harmonic function. Through a complex variable approach and a weakening technique, the analysis is reduced to solving a fundamental ordinary differential equation parameterized by a real constant k. The explicit integration of this ordinary differential equation involves various elliptic integrals and identities of elliptic functions. Solving the ordinary differential equation for the three cases: when the constant k equals zero, when k is greater than zero, and when k is less than zero yields the full classification of all admissible surfaces and their associated transformations. This process yields several classes of minimal surfaces that, to the best of the author's knowledge, constitute new families of minimal surfaces.
