{ "id": "2108.11705", "version": "v1", "published": "2021-08-26T11:03:12.000Z", "updated": "2021-08-26T11:03:12.000Z", "title": "New characterizations of the helicoid in a cylinder", "authors": [ "Eunjoo Lee" ], "comment": "15 pages, 5 figures", "categories": [ "math.DG" ], "abstract": "This paper characterizes a compact piece of the helicoid $H_C$ in a solid cylinder $C \\subset \\mathbb{R}^3$ from the following two perspectives. First, under reasonable conditions, $H_C$ has the smallest area among all immersed surfaces $\\Sigma$ with $\\partial \\Sigma \\subset d_1 \\cup d_2 \\cup S$, where $d_1$ and $d_2$ are the diameters of the top and bottom disks of $C$ and $S$ is the side surface of $C$. Second, other than $H_C$, there exists no minimal surface whose boundary consists of $d_1$, $d_2$, and a pair of \\textcolor{black}{rotationally symmetric} curves $\\gamma_1$, $\\gamma_2$ on $S$ along which it meets $S$ orthogonally. We draw the same conclusion when the boundary curves on $S$ are a pair of helices of a certain height.", "revisions": [ { "version": "v1", "updated": "2021-08-26T11:03:12.000Z" } ], "analyses": { "keywords": [ "characterizations", "solid cylinder", "smallest area", "boundary curves", "paper characterizes" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable" } } }