Spherical quadrilateral with three right angles and its application for diameter of extreme points of a convex body

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Lassak, Marek
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912452359225344
author Lassak, Marek
author_facet Lassak, Marek
contents We prove a theorem on the relationships between the lengths of sides of a spherical quadrilateral with three right angles. They are analogous to the relationships in the Lambert quadrilateral in the hyperbolic plane. We apply this theorem in the proof of our second theorem that if $C$ is a two-dimensional spherical convex body of diameter $δ\in (\frac{1}{2}π,π)$, then the diameter of the set of extreme points of $C$ is at least $2 \arccos \big(\frac{1}{4}(\cos δ+ \sqrt {\cos^2 δ+8})\big)$. This estimate cannot be improved.
format Preprint
id arxiv_https___arxiv_org_abs_2412_12388
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Spherical quadrilateral with three right angles and its application for diameter of extreme points of a convex body
Lassak, Marek
Metric Geometry
52A55
We prove a theorem on the relationships between the lengths of sides of a spherical quadrilateral with three right angles. They are analogous to the relationships in the Lambert quadrilateral in the hyperbolic plane. We apply this theorem in the proof of our second theorem that if $C$ is a two-dimensional spherical convex body of diameter $δ\in (\frac{1}{2}π,π)$, then the diameter of the set of extreme points of $C$ is at least $2 \arccos \big(\frac{1}{4}(\cos δ+ \sqrt {\cos^2 δ+8})\big)$. This estimate cannot be improved.
title Spherical quadrilateral with three right angles and its application for diameter of extreme points of a convex body
topic Metric Geometry
52A55
url https://arxiv.org/abs/2412.12388