Speaker
Description
The big-bang nucleo-synthesis (BBN) occurs in a relatively dense electron-positron e-ē plasma environment, kept in thermal equilibrium by a very dense photon γ background. We describe and evaluate the static and dynamic electromagnetic properties of this unique physical environment. The collisional thermal damping/relaxation rate in the plasma is found by calculating the net electron-positron scattering rate. The damping rate is much larger than the screening mass, indicating that the mean distance between collisions is much smaller than the Debye length. We further explore how the less dense protons and already formed other light nuclear “impurities” disturb this medium. We evaluate the inter-nuclear electromagnetic potentials arising from the e-ē-γ phase space fluctuations, subject to scattering damping and allowing for the dynamical motion of the EM-field surrounding this heavy nuclear ‘dust’: Interestingly, the EM potential of the dispersed nuclear dust in the e-ē plasma matches in its theoretical properties dusty plasma theory. In BBN temperature range for the subsonic movement of ions, we find that a wake charge forms in the rear leading to the total screening of the electric potential beyond a distance of around ∼ 10^3 fm.
