A Pseudoconfiguration of Points without Adjoint

✍ Scribed by W Hochstättler; S Kromberg

• Book ID: 102970860
• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 659 KB
• Volume: 68
• Category: Article
• ISSN: 0095-8956
• DOI: 10.1006/jctb.1996.0069

✦ Synopsis

We give an example of a simple oriented matroid D that admits an oriented adjoint. Furthermore, any adjoint of the underlying matroid D, does not itself admit an adjoint. D arises from the well-known non-Desargues matroid by a coextension by a coparallel element and, hence, has rank 4. The orientability of D and some of its adjoints follows from an apparently new oriented matroid construction given in the paper that is a very special case of an amalgam of two copies of one oriented matroid.

1996 Academic Press, Inc. situation is more difficult with ``pseudoconfigurations of points' ' (cf. [5, Chap. 5.3]).