Actions on positively curved manifolds and boundary in the orbit space

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Gorodski, Claudio, Kollross, Andreas, Wilking, Burkhard
Format: Preprint
Published: 2021
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914688313327616
author Gorodski, Claudio
Kollross, Andreas
Wilking, Burkhard
author_facet Gorodski, Claudio
Kollross, Andreas
Wilking, Burkhard
contents We study isometric actions of compact Lie groups on complete orientable positively curved $n$-manifolds whose orbit spaces have non-empty boundary in the sense of Alexandrov geometry. In particular, we classify quotients of the unit sphere by actions of compact simple Lie groups with non-empty boundary. We deduce from this the list of representations of compact simple Lie groups that admit non-trivial reductions. As a tool of special interest, we introduce a new geometric invariant of a compact symmetric space, namely, the minimal number of points in a "spanning set" of the space.
format Preprint
id arxiv_https___arxiv_org_abs_2112_00513
institution arXiv
publishDate 2021
record_format arxiv
spellingShingle Actions on positively curved manifolds and boundary in the orbit space
Gorodski, Claudio
Kollross, Andreas
Wilking, Burkhard
Differential Geometry
Representation Theory
57S15 53C21 53C35
We study isometric actions of compact Lie groups on complete orientable positively curved $n$-manifolds whose orbit spaces have non-empty boundary in the sense of Alexandrov geometry. In particular, we classify quotients of the unit sphere by actions of compact simple Lie groups with non-empty boundary. We deduce from this the list of representations of compact simple Lie groups that admit non-trivial reductions. As a tool of special interest, we introduce a new geometric invariant of a compact symmetric space, namely, the minimal number of points in a "spanning set" of the space.
title Actions on positively curved manifolds and boundary in the orbit space
topic Differential Geometry
Representation Theory
57S15 53C21 53C35
url https://arxiv.org/abs/2112.00513