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saviornt's avatar
saviornt
Protege
10 years ago

Quantum communications: It's coming!

Without going into the physics of it, ever want an internet speed that is equivalent of having it stored on your local computer? Well, it looks like there has been a pretty big leap in using quantum entanglement (having the properties of 1 electron effect another electron's properties instantaneously no matter the distance) for communications.

Within a few months China will be field testing a quantum communications network and satellite. Of course, it is for military and diplomatic communications, however, within a few years time I suspect that there will be a civilian version of the network.. just like how the internet first started.

http://www.marketwatch.com/story/china- ... 2015-02-09

It looks like the network has been lab tested for awhile now, since 2009. Its also worth it to note that there was a minor article about the USAF looking into it during that time. If we assume ~10 years between technology to become "civilianized", then civilian quantum networks will start appearing in 2018-2026.

This is also in my predicted timeframe for VR to become "mainstream". Interesting times for sure 8-)

5 Replies

  • MrMonkeybat's avatar
    MrMonkeybat
    Explorer
    10 years ago
    The satellite would be used to transmit encoded data through a method called quantum key distribution (QKD), which relies on cryptographic keys transmitted via light-pulse signals. QKD is said to be nearly impossible to hack, since any attempted eavesdropping would change the quantum states and thus could be quickly detected by data-flow monitors.


    The quantum part is for encryption, apart from that it is no better than any other optical communication. If you where expecting some kind of ansible communication device wireless and occlusion free those who know more about quantum physics than me say it is impossible to transmit information through entanglement.
  • saviornt's avatar
    saviornt
    Protege
    10 years ago
    That's the encryption side of it, yes, however, not only can they send the keys through entanglement, they can also send packets the same way.

    However, due to the FiO approach that they are using, the initial link would only be as fast as what the fibre channel is. After the initial entanglement is done, communication to and from should be instantaneous.. at least, if they are using true entanglement and not some hybrid form of it.
  • MrMonkeybat's avatar
    MrMonkeybat
    Explorer
    10 years ago
    Entanglement does not work that way, as soon as you measure the particle entanglement ends. So you know the other guy reads the opposite spin, but the spin is random there is no way to force the other particle to have the spin you want to give some kind of message.
    http://io9.com/5584356/can-i-build-an-a ... the-cosmos
  • obzen's avatar
    obzen
    Expert Protege
    10 years ago
    I like Jim al Khalili's analogy, although I'm sure the analogy is somewhat stretched.

    Anyway, the particle is a spinning coin, neither heads nor tail. The only way to know is basically slam the coin to force it to become one or the other. Then you also know the face facing down will be the opposite of face facing up. But you have a 50-50 of getting either heads or tail with no way of pre-determining the outcome reliably (with assumption that you are not cheating or possess superhuman abilities, hence the analogy part).
  • saviornt's avatar
    saviornt
    Protege
    10 years ago
    "obzen" wrote:
    I like Jim al Khalili's analogy, although I'm sure the analogy is somewhat stretched.

    Anyway, the particle is a spinning coin, neither heads nor tail. The only way to know is basically slam the coin to force it to become one or the other. Then you also know the face facing down will be the opposite of face facing up. But you have a 50-50 of getting either heads or tail with no way of pre-determining the outcome reliably (with assumption that you are not cheating or possess superhuman abilities, hence the analogy part).


    That's the quantum state. Quantum entanglement is a different beast altogether.