Discrete & Computational Geometry

, Volume 4, Issue 2, pp 97–100 | Cite as

Uniform oriented matroids without the isotopy property

  • Beat Jaggi
  • Peter Mani-Levitska
  • Bernd Sturmfels
  • Neil White


We give an easy general construction for uniform oriented matroids with disconnected realization space. This disproves the longstanding isotopy conjecture for simple line arrangements or order types in the plane.


Discrete Comput Geom Order Type Convex Polytopes Oriented Matroids Continuous Surjection 
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Copyright information

© Springer-Verlag New York Inc. 1989

Authors and Affiliations

  • Beat Jaggi
    • 1
  • Peter Mani-Levitska
    • 1
  • Bernd Sturmfels
    • 2
  • Neil White
    • 3
  1. 1.Mathematisches Institut der Universität BernBernSwitzerland
  2. 2.Research Institut for Symbolic ComputationJohannes-Kepler UniversitätLinzAustria
  3. 3.Department of MathematicsUniversity of FloridaGainesvilleUSA

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