  Understanding quantum dynamics in a two-dimensional Bose-Einstein condensate
(BEC) relies on understanding how vortices interact with each others
microscopically and with local imperfections of the potential which confines
the condensate. Within a system consisting of many vortices, the trajectory of
a vortex-antivortex pair is often scattered by a third vortex, an effect
previously characterised. However, the natural question remains as to how much
of this effect is due to the velocity induced by this third vortex and how much
is due to the density inhomogeneity which it introduces. In this work, we
describe the various qualitative scenarios which occur when a vortex-antivortex
pair interacts with a smooth density impurity whose profile is identical to
that of a vortex but lacks the circulation around it.
