College of Liberal Arts & Sciences

# Math Physics Seminar

**Abstract:**

Electromagnetic probes are a useful tool for studying the dynamics of hadronic particles. This is because in the one-photon exchange approximation the scattering matrix elements are linear in the matrix elements of the hadronic current operator. Realistic phenomenological models of hadronic systems can provide both spectral and scattering observables that are consistent with experiment for various nuclei.

To study these models with electromagnetic probes it is necessary to have models of the electric current of the hadrons that are consistent with the model interaction. Relativistic covariance and current conservation cannot be satisfied by assuming that the hardonic current is the sum of single-hadron currents, however satisfying these two conditions does not fix the current. In this talk I propose a method to construct many body-hadronic currents operators that are consistent with the model interactions by using the Weyl representation to construct a gauge invariant extension of the dynamics by replacing the momentum operators in the Weyl representation of the interaction by gauge covariant derivatives.