@article{2012-ma-zeilinger-pnas-v110-p1221,
	Abstract = {The counterintuitive features of quantum physics challenge many common-sense assumptions. In an interferometric quantum eraser experiment, one can actively choose whether or not to erase which-path information (a particle feature) of one quantum system and thus observe its wave feature via interference or not by performing a suitable measurement on a distant quantum system entangled with it. In all experiments performed to date, this choice took place either in the past or, in some delayed-choice arrangements, in the future of the interference. Thus, in principle, physical communications between choice and interference were not excluded. Here, we report a quantum eraser experiment in which, by enforcing Einstein locality, no such communication is possible. This is achieved by independent active choices, which are space-like separated from the interference. Our setup employs hybrid path-polarization entangled photon pairs, which are distributed over an optical fiber link of 55 m in one experiment, or over a free-space link of 144 km in another. No naive realistic picture is compatible with our results because whether a quantum could be seen as showing particle- or wave-like behavior would depend on a causally disconnected choice. It is therefore suggestive to abandon such pictures altogether.},
	Author = {Ma, X. AND Kofler, J. AND Qarry, A. AND Tetik, N. AND Scheidl, T. AND Ursin, R. AND Ramelow, S. AND Herbst, T. AND Ratschbacher, L. AND Fedrizzi, A. AND Jennewein, T. AND Zeilinger, A.},
	Journal = {PNAS },
	Pages = {1221},
	Title = {{Quantum erasure with causally disconnected choice}},
	Volume = {110},
	Year = {2012}
}