From buildings to point-line geometries and back again (Q447759)

The author surveys results about geometries and chamber systems, in particular those associated to buildings. He describes a construction due to Pasini to assign to a building and a type of points-to-be a Grassmannian, which is a point-line geometry. He then goes on to consider the inverse problem, namely given a point-line geometry to determine in which way it can arise as a Grassmannian. In answering this question he concentrates on parapolar spaces, which were introduced by Cohen.