Maximal cocliques in the Kneser graph of point-line flags in PG(4,q)

We determine the maximal cocliques of size >_ 4q2 + 5q + 5 in the Kneser graph on point-plane ags in PG(4; q). The maximal size of a coclique in this graph is (q2 + q + 1)(q3 + q2 + q + 1)

Cocliques in the Kneser graph on the point-hyperplane flags of a projective space

We prove an Erdos-Ko-Rado-type theorem for the Kneser graph on the point-hyperplane flag in a finite projective space