Abstract:
The two-photon ghost interference experiment, generalized to the case of massive particles,
is theoretically analyzed. It is argued that the experiment is intimately connected to
a double-slit interference experiment where, which-path information exists. The reason for
not observing first order interference behind the double-slit, is clarified. It is shown that
the underlying mechanism for the appearance of ghost interference is, the more familiar,
quantum erasure.