Orbifold homeomorphism finiteness based on geometric constraints Authors Emily Proctor Department of Mathematics Middlebury College Original Paper

First Online: 24 May 2011 Received: 01 March 2011 Accepted: 19 April 2011 DOI :
10.1007/s10455-011-9270-4

Cite this article as: Proctor, E. Ann Glob Anal Geom (2012) 41: 47. doi:10.1007/s10455-011-9270-4
Abstract
We show that any collection of n -dimensional orbifolds with sectional curvature and volume uniformly bounded below, diameter bounded above, and with only isolated singular points contains orbifolds of only finitely many orbifold homeomorphism types. This is a generalization to the orbifold category of a similar result for manifolds proven by Grove, Petersen, and Wu. It follows that any Laplace isospectral collection of orbifolds with sectional curvature uniformly bounded below and having only isolated singular points also contains only finitely many orbifold homeomorphism types. The main steps of the argument are to show that any sequence from the collection has subsequence that converges to an orbifold, and then to show that the homeomorphism between the underlying spaces of the limit orbifold and an orbifold from the subsequence that is guaranteed by Perelman’s stability theorem must preserve orbifold structure.

Keywords
Orbifold
Global Riemannian geometry
Alexandrov space
Spectral geometry

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