QUEST FOR GHZ STATES

The premises of the Einstein-Podolsky-Rosen argument for their claim t hat quantum mechanics is an incomplete theory are inconsistent when ap plied to three-particle systems in entangled Greenberger-Horne-Zeiling er states. However, thus far there is no experimental confirmation for existence of such states. We propose a technique to obtain Greenberge r-Horne-Zeilinger states which rests upon an observation that when a s ingle particle from two independent entangled pairs is detected in a m anner such that it is impossible to determine from which pair the sing le came, the remaining three particles become entangled.