An operator definition of collisional energy and momentum loss in relativistic plasmas

This talk will present work performed over the last couple of years at LANL on developing an operator definition/derivation of collisional energy and momentum loss suffered by an energetic charged particle in the presence of a medium. The approach uses the energy-momentum tensor of the medium to evaluate the energy and momentum transfer rates. We apply this formalism to an energetic lepton or quark propagating in thermal electron-positron or quark-gluon plasmas, respectively. We show explicitly that the operator method reproduces the known results for collisional energy loss from the scattering rate formalism. In the last part of the talk we will change directions a bit. I will discuss some of the interesting physics we work on at EMA related to lightning strikes on aircraft.