  Quantum systems in specific regimes display recurrences at the period of the
periodic orbits of the corresponding classical system. We investigate the
excited hydrogen atom in a magnetic field -- a prototypical system of 'quantum
chaos' -- from the point of view of the de Broglie Bohm (BB) interpretation of
quantum mechanics. The trajectories predicted by BB theory are computed and
contrasted with the time evolution of the wavefunction, which shows pronounced
features at times matching the period of closed orbits of the classical
hydrogen in a magnetic field problem. Individual BB trajectories do not possess
these periodicities and cannot account for the quantum recurrences. These
recurrences can however be explained by BB theory by considering the ensemble
of trajectories compatible with an initial statistical distribution, although
none of the trajectories of the ensemble are periodic, rendering unclear the
dynamical origin of the classical periodicities.
