Singularity of mean curvature flow with bounded mean curvature and Morse index
Yongheng Han
TL;DR
This work analyzes singularity formation in mean curvature flow for closed smooth embedded hypersurfaces in $\mathbb{R}^{n+1}$ under uniform bounds on the mean curvature and Morse index. It proves that in dimensions $3\le n\le 6$ the first singular time cannot feature uncontrolled blow-up: either $|H|$ or the index must diverge, and the flow converges to a limit with multiplicity one away from a small singular set; the singular set has Minkowski dimension at most $n-7$ and rescaled flows converge to stable minimal cones of multiplicity one. The authors develop a weak-compactness framework for hypersurfaces and flows, construct auxiliary functions to capture stability, and establish a multiplicity-one convergence for the rescaled flow via a detailed space-decomposition and $L$-stability arguments. These results sharpen the understanding of the local and global structure of singularities in mean curvature flow and connect to the broader theory of self-shrinkers and Brakke flows.
Abstract
We study the multiplicity of the singularity of mean curvature flow with bounded mean curvature and Morse index. For $3\leq n\leq 6$, we show that either the mean curvature or the Morse index blows up at the first singular time for a closed smooth embedded mean curvature flow in $\mathbb{R}^{n+1}$.
