Self-dual metrics with maximally superintegrable geodesic flows

A class of self-dual and geodesically complete spacetimes with maximally superintegrable geodesic flows is constructed by applying the Eisenhart lift to mechanics in pseudo-Euclidean spacetime of signature (1,1). It is characterized by the presence of a second-rank Killing tensor. Spacetimes of the ultrahyperbolic signature (2,q) with q>2, which admit a second-rank Killing tensor and possess superintegrable geodesic flows, are built.