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The shape of the electron is studied using lowest-order perturbation theory.Quantities used to probe the structure of the proton: form factors, generalizedparton distributions, transverse densities, Wigner distributions and theangular momentum content are computed for the electron-photon component of theelectron wave function. The influence of longitudinally polarized photons,demanded by the need for infrared regularization via a non-zero photon mass, isincluded. The appropriate value of the photon mass depends on experimentalconditions, and consequently the size of the electron (as defined by the slopeof its Dirac form factor) bound in a hydrogen atom is found to be about fourtimes larger than when the electron is free. The shape of the electron, asdetermined from the transverse density and generalized parton distributions isshown to not be round, and the free electron is shown to be far less round thanthe bound electron. An electron distribution function (analogous to the quarkdistribution function) is defined, and that of the bound electron is shown tobe suppressed compared to that of the free electron. If the relative transversemomentum of the virtual electron and photon is large compared with the electronmass, the virtual electron and photon each carry nearly the total angularmomentum of the physical electron (1/2), with the orbital angular momentumbeing nearly (-1/2). Including the non-zero photon mass leads to thesuppression of end-point contributions to form factors. Implications for protonstructure and color transparency are discussed.

Electron Structure: Shape, Size and GPDs in QED