Talk page

Title:
A counterexample to the extension space conjecture for realizable oriented matroids

Speaker:
Xue Liu

Abstract:
The extension space conjecture, proposed by Sturmfels and Ziegler in 1993, is a conjecture about the topology of a realizable oriented matroid's "extension space", which is a topological model for the set of all extensions of the oriented matroid by a single element. Equivalently, it is a conjecture about the poset of proper zonotopal tilings of a zonotope, namely that this poset is homotopy equivalent to a sphere. In this talk we describe a counterexample to this conjecture in three dimensions.

Link:
https://www.msri.org/workshops/819/schedules/23152

Workshop:
MSRI- Geometric and topological combinatorics: Modern techniques and methods