Interesting pointsets in generalized quadrangles and partial geometries
The author considers subsets of the point set of a generalized quadrangle with the property that each line intersects the subset in a constant number of points; more generally, the analogous problem is considered for partial geometries. He also studies arcs in generalized quadrangled and partial geometries. The proofs of the results (which typically involve inequalities on the parameters) use a matrix technique which is also applied to give an elementary proof for the Krein inequalities for strongly regular graphs.
scientific article; zbMATH DE number 4083639
scientific article