Discrete & Computational Geometry

, Volume 49, Issue 2, pp 287–295 | Cite as

New Examples of Oriented Matroids with Disconnected Realization Spaces



We construct oriented matroids of rank 3 on 13 points whose realization spaces are disconnected. They are defined on smaller point-sets than the known examples with this property. Moreover, we construct one on 13 points whose realization space is a connected but non-irreducible semialgebraic variety.


Oriented matroids Realization space 


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© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Department of Human CoexistenceKyoto UniversityKyotoJapan

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