Relativistic effects and relativistic methods

In the past, the vast majority of nuclear physics calculations were carried out using nonrelativistic quantum mechanics. Relativistic effects were usually regarded as small corrections, primarily kinematic in origin. However, as understanding of hadronic matter has developed, and as high energy accelerators capable of probing hadronic systems to very high momenta become available, interest in relativistic methods has grown and theoretical techniques have matured. Until the early 1980's, most research was centered on methods for computing relativistic corrections to calculations which are essentially non-relativistic. The idea was to find corrections to lowest order in (v/c){sup 2}, where v is a typical particle velocity regarded as small compared to nuclear energies and masses. Recent work goes far beyond such expansion methods. Fully covariant approaches, in which the dynamics is closely connected to field theory, are now being developed