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Comment by mtgx | Hacker News Reader

They're already working on quantum communications between Earth and satellites, too, but it's obviously still very early days. But it will probably be what we'll use for very large distances in the future.

http://www.extremetech.com/extreme/152906-european-scientist...

http://spectrum.ieee.org/tech-talk/aerospace/satellites/chin...

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'Quantum communications' isn't a real thing outside of scifi (and generally the crappier kind).

It's sometimes (inaccurately) used to describe quantum entanglement (or quantum encryption) but it doesn't actually allow for the transfer of information.

It can be used for quantum encryption but the actual information transfer has to take place over a traditional medium. When you hear those stories about quantum teleportation and such that is generally what they are talking about.

As I understand it, this is about "secure" communications and not some magical new way of information transmission. These "quantum communications" would still require a standard channel to communicate over.... which would likely be laser/radio as per normal.

Do you need that for quantum entanglement communication, too?

From various discussions I've had with physicists on the matter I found the answer is yes.

My thoughts were summed up by having a device here on earth that is entangled with a device just above the surface of the sun. Now imagine the sun vanishes and the devices communicate this information over the entanglement, thus (to my mind) breaking the "light barrier" as we receive an 8 minute warning that the lights have gone out. I don't fully remember (or understand!) the answer I got, but it most definitely had a reliance upon a relativistic communication channel.

[also: what H3g3m0n said - entanglement is not about the transfer of information]

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