Almgren's Three-Legged Starfish
Differential Geometry
2025-04-30 v1
Abstract
In this note we use classical tools from min-max and hyperbolic geometry to substantiate a folklore example in Almgren--Pitts min-max theory, the three-legged starfish metric on a 2-sphere, whose systolic length, Almgren--Pitts width, and Gromov--Guth width are attained by ``figure-eight'' geodesics. We also recover a hyperbolic geometry fact about ``figure-eight'' geodesics using min-max.
Cite
@article{arxiv.2504.20895,
title = {Almgren's Three-Legged Starfish},
author = {Christos Mantoulidis and Jared Marx-Kuo},
journal= {arXiv preprint arXiv:2504.20895},
year = {2025}
}
Comments
8 pages, 1 figure, comments welcome!