Vacuum-induced oscillations in the charge density of distinguishable fermions

¹  Intense Laser Physics Theory Unit and Department of Physics, Illinois State University Normal, IL 61790-4560, USA
²  Department of Physics and Astronomy, Lehman College - Bronx, NY 10468-1589, USA

Received: 2 September 2008
Accepted: 23 October 2008

Abstract

We have computed the time-dependent charge density for a fermionic two-particle system. In classical electrodynamics the total charge density is given by the sum of the individual densities associated with each particle. This intuitive relationship changes in quantum field theory if the particle pair was created from the vacuum. In this case the presence of the vacuum can lead to high-frequency oscillations in the resulting charge density. We note the modulation in the density outside the region where the pair is created may be interesting for probing the fermionic vacuum.