DATE:     4/21/05
TIME:     12:10 pm in Weber 117
SPEAKER:  Rieuwert Blok (CSU)
TITLE:    The opposite complex in buildings

ABSTRACT: The complex of objects/chambers "opposite to" or "at maximal
distance from" a given chamber or residue plays a central role in the
classification of (Moufang) buildings.  It continues to be of
importance. For instance it has been used in a proof of the
Curtis-Phan-Tits theorem by Bennett et al. I will discuss this
complex, its study and some applications from a geometric and group
theoretic point of view.