Entanglement in time

Question

Quantum entanglement links particles through time, according to this study that received some publicity last year:

• New Type Of Entanglement Allows 'Teleportation in Time,' Say Physicists at The Physics arXiv Blog - Technology Review
• S.J. Olson, T.C. Ralph, Extraction of timelike entanglement from the quantum vacuum, arXiv:1101.2565
• S.J. Olson, T.C. Ralph, Entanglement between the Future and the Past in the Quantum Vacuum, Phys. Rev. Lett. 106, 110404 (2011)

  Timelike entanglement may be regarded as a non-classical resource in a manner analogous to the spacelike entanglement that is often studied in the Minkowski vacuum, since any quantum information theoretic protocol may utilize conversion of timelike entanglement to spacelike entanglement as a step in the protocol.

I have read all the reviews in the popular press, most of the "time-travel-discovered" type, but I am looking for more sober comments, i.e. material written by physicists who have studied the paper. What does this result really mean? I would appreciate pointers to reviews, comments etc.

Answer 1

I would venture that the paper is less significant than it seems, since in a universe with special relativity, what looks like a successful experimental proof of spatial entanglement to one observer will always look like a mix of space and time entanglement to another one.