Speaker
Description
The Lorentz group of special relativity contains a Galilean subgroup, under which light front time is invariant. Using the light front time variable along with the ordinary three Cartesian spatial coordinates allows a fully relativistic spatial description of the internal structure of hadrons, specifically in the form of two-dimensional densities on the plane transverse to the observer's line of sight. This description is frame-independent, and thus provides a rest-frame picture of the hadron's charge, current, energy, momentum and stress distributions. The use of the light front time variable is physically interpreted as providing an alternative time synchronization convention, and the use of the usual three spatial coordinates allows all components of the electromagnetic four-current and the energy-momentum tensor to be given a clear physical interpretation. Densities of pions and nucleons are presented as examples.
