Abstract
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.
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The research of Bernd Sturmfels and Neil White was supported in part by the Institute for Mathematics and Its Applications with funds provided by the National Science Foundation.
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Jaggi, B., Mani-Levitska, P., Sturmfels, B. et al. Uniform oriented matroids without the isotopy property. Discrete Comput Geom 4, 97–100 (1989). https://doi.org/10.1007/BF02187717
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DOI: https://doi.org/10.1007/BF02187717