Advance opens door for secure quantum applications without specialized infrastructure

  • mPony@lemmy.world
    link
    fedilink
    English
    arrow-up
    3
    arrow-down
    2
    ·
    2 hours ago

    #Hey Kids! Guess which word is getting shoehorned into EVERY technology discussion in 2025 until it becomes meaningless?

  • Opisek@lemmy.world
    link
    fedilink
    English
    arrow-up
    2
    ·
    edit-2
    3 hours ago

    So they’ve shown they can send light over a cable designed to transfer light.

    The impressive thing is of course managing to get one specific photon to one specific location. Still, what benefits does that have over the standard encoding?

    I guess this technique might have a lower error rate and higher distance, because it’s binary by nature with no quantization needed. But you don’t need the quantum entanglement part at all for this.

    Edit: Reading is hard! This is indeed exciting for security. I wonder how it fairs against a very powerful MitM though.

  • FiskFisk33@startrek.website
    link
    fedilink
    English
    arrow-up
    11
    arrow-down
    1
    ·
    edit-2
    6 hours ago

    Only limited by the speed of light,

    What exactly do you think the normal ip data is limited by on the same optical cable?

    I thought we were talking about quantum entaglement and spooky action at a distance, which is famously not limited by the speed of light?

    Am I missing something obvious?

    • htrayl@lemmy.world
      link
      fedilink
      English
      arrow-up
      8
      ·
      5 hours ago

      Yes, quantum entanglement occurs without the speed of light, but we famously cannot interpret information from it faster than the speed of light - it isn’t FTL communication.

  • kayzeekayzee@lemmy.blahaj.zone
    link
    fedilink
    English
    arrow-up
    47
    arrow-down
    3
    ·
    edit-2
    18 hours ago

    The article starts by doing the “quantum” thing that really irks me, where they use confusing terminology to make it sound like “FTL communication” without actually saying it. This is garbage that doesn’t actually matter to the article.

    Basically, they found a way to send quantum entangled photons (which exist in a very delicate unobserved state) through existing fiber optic infrastructure without interfering with the standard internet information already travelling through the fiber. A lot of the difficulty with this is due to signal noise that needs to be filtered out. This will be useful communicating quantum measurements over long distances.

      • 4am@lemm.ee
        link
        fedilink
        English
        arrow-up
        9
        arrow-down
        4
        ·
        13 hours ago

        They then go on to describe what sounds like

        • transmitting a single specific photon through ‘the internet’, implying start-to-finish with routing (not possible without special infrastructure)

        • Use that photon to then send information instantly by manipulating its entangled sibling (also not possible)

        So yeah this article is a crock of shit.

    • slackassassin@sh.itjust.works
      link
      fedilink
      English
      arrow-up
      4
      arrow-down
      1
      ·
      17 hours ago

      The article starts by doing the “quantum” thing that really irks me

      Basically, they found a way to send quantum entangled photons

  • partial_accumen@lemmy.world
    link
    fedilink
    English
    arrow-up
    30
    ·
    edit-2
    14 hours ago

    This is a cool progress forward.

    TLDR; Researchers used a 30km optical fiber. They found a wavelength that was off-to-the-side that would mean the quantum entangled photons could ride in the same fiber without interfering (or being interfered with) the classical fiber optic communications. One current shortcoming for scaling this up is that the quantum photons would not survive optical repeaters commonly used for extremely long distant fiber runs. That doesn’t take away from the success of their research, just puts it in perspective for the next researchers to tackle at some point in the future.

    • Hello Hotel@lemmy.world
      link
      fedilink
      English
      arrow-up
      9
      ·
      edit-2
      18 hours ago

      Is the reason (Im assuming you ment) it can’t survive a repeater survive a repeater because it collects and recreates the particle? These cables are ment for logical data transport.

      • partial_accumen@lemmy.world
        link
        fedilink
        English
        arrow-up
        8
        ·
        17 hours ago

        Yes. Keep in mind nothing in the article talks about the fiber repeater. That is my addition with some knowledge of telecommunications infrastructure. Because fiber optic cable isn’t perfect, there is light loss over distance. Different grades of fiber have different levels of loss across distance. An example of high end fiber would be ZBLAN. There is experimental level manufacturing (successful in small quantities already) of producing ZBLAN fiber in space to improve the fiber quality, but that makes it much more expensive. Once the limits of the fiber are reached a telecommunications provider can place a fiber repeater to double the length by intercepting the light (signal) and reproducing it (blinking new laser light) into the next segment of fiber.

        However, these repeaters create NEW light, and that would mean the quantum information is not carried over in present day fiber repeaters. Even measuring the entangled photon to recreate it would break the quantum state of the entangled photon at the source, so current means can’t be used as a repeater for quantum data.

  • JoShmoe@ani.social
    link
    fedilink
    English
    arrow-up
    4
    arrow-down
    8
    ·
    18 hours ago

    If I understand it right, this could enable real time connectivity between client and server.

    • knightly the Sneptaur@pawb.social
      link
      fedilink
      English
      arrow-up
      29
      ·
      edit-2
      12 hours ago

      Nope, quantum entanglement can’t enable FTL communication. “Real time” still involves lightspeed lag.

      What it does is allows random bits of information to be transmitted in an entangled state. You send an entangled pair of photons, and find out afterwards who got a 1 or a 0 when the photons are observed at either end. They call it ‘quantum teleportation’ because both ends know what the other got, and the information about who got what can’t be intercepted without disrupting the enganglement.

      Once they can figure out how to preserve that uncertainty through repeaters, switches, and routers, then we can have a quantum internet that uses encryption based on shared quantum random numbers. It’s likely to be necessary soon since quantum computers might only be a few years from breaking current common encryption techniques.