4 papers
Lexicographic Extensions preserve Euclideaness
Winfried Hochstättler, Michael Wilhelmi
We prove that a lexicographical extension of a Euclidean oriented matroid remains Euclidean.
Independent Hyperplanes in Oriented Paving Matroids
Lamar Chidiac, Winfried Hochstättler
In 1993, Csima and Sawyer proved that in a non-pencil arrangement of n pseudolines, there are at least simple points of intersection. Since pseudoline arrangements…
On the Geometry of Holmsen's Combinatorial Version of the Colorful Carathéodory
Helena Bergold, Winfried Hochstättler
Carathéodorys Theorem of convex hulls plays an important role in convex geometry. In 1982, Bárány formulated and proved a more general version, called the Colorful Carathéodory. Th…
Lattice Path Matroids are 3-Colorable
Immanuel Albrecht, Winfried Hochstättler
We show that every lattice path matroid of rank at least two has a quite simple coline, also known as a positive coline. Therefore every orientation of a lattice path matroid is 3-…