Abstract
A measurement has been made of the relative linear polarization of the two photons produced from s-state positron-electron annihilation. This is an example of a quantum system consisting of the widely separated components, which were previously closely spatially linked with one another. Compton polarimeters were used to detect the planes of polarization. Prime interest was attached to whether the correlation between the planes of polarization changed with increasing source-polarimeter separations when the source was placed symmetrically between the two polarimeters. Measurements were also made for substantial differences in the separations. No significant change in the correlation was observed over separations of up to 2.5 m and over differences in separation of about 1 m.