  We discuss a recently proposed extension of Bohmian mechanics to quantum
field theory. For more or less any regularized quantum field theory there is a
corresponding theory of particle motion, which in particular ascribes
trajectories to the electrons or whatever sort of particles the quantum field
theory is about. Corresponding to the nonconservation of the particle number
operator in the quantum field theory, the theory describes explicit creation
and annihilation events: the world lines for the particles can begin and end.
