Interaction between a caviy and a singularity in nematics

Abstract

It is shown that a singularity of strength s interacts with a cylindrical cavity having uniform boundary conditions, as though instead of the cylindrical cavity there is a singularity of strength s at the conjugate point together with one of strength (l - s) at the centre. At large distances the cavity acts as a disclination of strength + 1. Disclinations of negative strength form dipoles with the cavity. An extension of this result can account for the interaction between a spherical cavity and a singular point.