Remote which-way-choice scheme: proposed foundations experiments
  Twin photons from spontaneous parametric down-conversion with preselected polarization are used as spatially disjoint subsystems. One photon is subject to an interference measurement, while a projective measurement of the second photon induces the way-choice of the first photon. This would be an example of way-choice free of direct action on the interfering photon. Two further applications of the proposed scheme are considered: a new method of quantum information speed measurement, and a test of commutation of space-like remote measurements. 
Artur Szczepanski