Consistency for the surface diffusion flat flow in three dimensions
Marco Cicalese, Nicola Fusco, Vesa Julin, Andrea Kubin
TL;DR
This work establishes the short-time consistency of a constrained minimizing movements scheme for the surface diffusion flow in three dimensions. By proving a higher-order geometric inequality and deriving uniform $H^4$-regularity for the discrete flat flow, the authors show that the scheme converges to the unique smooth solution of $V_t = \Delta_{\partial E_t} H_{E_t}$ for $C^5$-regular initial sets, with aδ-constraint that becomes irrelevant at small times. An Iteration Lemma provides a robust dissipation-control mechanism, enabling a bootstrap to high regularity and enabling convergence in $C^{2,\alpha}$ while preserving volume. The results offer a first rigorous bridge between the minimizing movements framework and classical surface-diffusion dynamics, and they extend to the flat torus, with implications for weak solutions and weak-strong uniqueness in this geometric flow context.
Abstract
We investigate the flat flow solution for the surface diffusion equation via the discrete minimizing movements scheme proposed by Cahn and Taylor. We prove that in dimension three the scheme converges to the unique smooth solution of the equation, provided that the initial set is sufficiently regular.
