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German Scientists Successfully Teleport Classical Information (upi.com)
An anonymous reader writes from an article on UPI: Using a series of laser beams, a pair of German scientists teleported information without the transfer or matter of energy. "Elementary particles such as electrons and light particles exist per se in a spatially delocalized state," Alexander Szameit, a professor at the University of Jena, explained in a press release. Classical information is coupled using a process called "entanglement." "As can be done with the physical states of elementary particles, the properties of light beams can also be entangled," said research Marco Ornigotti. "You link the information you would like to transmit to a particular property of the light." Researchers used polarization to encode information within a laser beam, enabling the teleportation of information instantly and in its entirety without loss of time. Whereas quantum information and quantum systems describe particle properties that are inferred, classical information describes physical properties directly measured.
From the press release: "With this form of teleportation, we can, however, not bridge any given distance," admits Szameit. "On the contrary, classic teleportation only works locally." http://www.uni-jena.de/en/Rese...
If time is relative, then it would seem to reason that causality would have to be at best local to one's own time frame.
Only it doesn't work like that at all in relativity: causality is preserved by the fact that information cannot travel faster than light. If you can transmit information faster than this then you can create real paradoxes which are not at all explainable i.e. events which occur in one reference frame and which do not occur in another because someone stopped them. This is not something which has ever been observed.
My guess is that the information speed is actually less than, or equal, to that of light because we have seen this sort of thing before with tunnelling photons. A photon can tunnel through a potential barrier faster than light but the chance that it makes it is less than 100%. This means that you have to send many photons to be sure the signal is transmitted and by the time you do that the average speed of information transmission has dropped to the speed of light even though single photons are faster.
I don't know the details of this experiment yet but I very, very strongly doubt that they actually transmit "actionable" information (i.e. information that could influence an observer's actions) at FTL speeds and I expect that the summary misread and misunderstood the results.
Flight takes many decades, but they stay in contact with earth in realtime.
This utterly breaks causality. For example suppose a terrorist had planted a bomb on the ship and uses this instant signal to detonate it. However nearby our hero Buzz Lightyear is cruising in the opposite direction at a large fraction of the speed of light. He sees the ship explode but in his frame of reference the terrorist of Earth has not actually pushed the button yet so he carries on flying to Earth and shoots the terrorist before the signal is sent....so why did the ship explode? ...and if it didn't explode why did Buzz fly to Earth and shoot someone?
The moment you have FTL information transmission you have time travel: the two are inextricably linked in relativity and the moment you have time travel you have causality violations. So either this experiment does not transmit actionable information FTL or there is a serious flaw with relativity. The later would be an extraordinary claim which requires extraordinary evidence.
They didn't figure out "non-local data transmission at FTL speeds".
They figured out local transmission without loss of time, i.e. encoding information into the polarization of a light beam, instantaneously, but without bridging any distance.
Quote: "With this form of teleportation, we can, however, not bridge any given distance," admits Szameit. "On the contrary, classic teleportation only works locally."
The rest is just the usual hyperbole and Star Trek comparisons by people who don't know what they're talking about. "Teleportation works instantly across any distance!" – yes, but not that kind of teleportation. The kind that works across distances cannot be used to transmit information.
No, the article was just written by a completely clueless person who had no idea what they were talking about. I looked up the original paper, and the answer is right there in the abstract:
For many years, however, it has been implicitly assumed that this scheme is of inherently nonlocal nature, and therefore exclusive to quantum systems[...] We present an optical implementation of the teleportation protocol solely based on classical entanglement between spatial and modal degrees of freedom, entirely independent of nonlocality.
This effect is, in their words, "entirely independent of nonlocality." The information is being transmitted through space in the ordinary way, traveling no faster than light. The person who wrote the summary just made up the part about "instantly" and "without loss of time."
"I'm too busy to research this and form an educated opinion, but I do have time to tell everyone my uninformed opinion."