Gaku Liu (MPI MIS, Leipzig)
Tuesday, January 16, 2018 - 11:00
MPI für Mathematik in den Naturwissenschaften Leipzig
Inselstr. 22, 04103 Leipzig, E1 05 (Leibniz-Saal), 1. Etage
The extension space conjecture of oriented matroid theory states that the space of all one-element, non-loop, non-coloop extensions of a realizable oriented matroid of rank d has the homotopy type of a sphere of dimension d 1. We disprove this conjecture by showing the existence of a realizable uniform oriented matroid of high rank and corank 3 with disconnected extension space. The talk will not assume any prior knowledge of oriented matroids.
submitted by Saskia Gutzschebauch (Saskia.Gutzschebauch@mis.mpg.de, 0341 9959 50)