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Archiv der Mathematik

, Volume 98, Issue 6, pp 571–581 | Cite as

Ptolemy circles and Ptolemy segments

  • Thomas FoertschEmail author
  • Viktor Schroeder
Article
  • 191 Downloads

Abstract

In this paper we characterize Ptolemy circles and Ptolemy segments up to isometry. Moreover, we present an example of a metric sphere, which is Möbius equivalent but not homothetic to the standard metric sphere with its chordal metric.

Keywords

Triangle Inequality Cross Ratio Convex Curve Unbounded Component Busemann Function 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Basel AG 2012

Authors and Affiliations

  1. 1.Institut für MathematikUniversität ZürichZürichSwitzerland

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