Geodesics in \(G_ 2^ 4\) (Q1332156)

It is known [the author, Inf. Sci. 40, 75-82 (1986; Zbl 0621.94004)] that multiple target angular determination for a radar array problem is equivalent to determining an \(r\)-dimensional subspace of \(n\)-space or a point in the Grassmannian \(G^ n_ r\). In this paper the case of \(G^ 4_ 2\) is considered. A metric suggested by the above problem is introduced in \(G^ 4_ 2\) and it is proved that the 8-dimensional Hamiltonian system for geodesics is completely integrable.