I just read this paper.
http://www.nature.com/ncomms/2014/140619/ncomms5145/full/ncomms5145.html.
ABSTRACT:
Experimental simulation of closed timelike curves
Martin Ringbauer1,2, Matthew A. Broome1,2, Casey R. Myers1, Andrew G. White1,2 & Timothy C. Ralph2
Closed timelike curves are among the...