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The Internet Science

A Successful Experiment Gets Us One Step Closer To a Quantum Internet (engadget.com) 42

Posted by BeauHD from the sci-fi-to-reality dept.
Earlier this week, a team of researchers announced that they successfully teleported qubits of photons across approximately 27 miles of fiber-optic cable. Engadget reports: While other scientists have worked on similar projects, this group is the first to beam quantum information across such a great distance. What's more, they did so across two separate networks and with a fidelity greater than 90 percent. One of the researchers on the team told Motherboard they built the networks using "off-the-shelf" components, and that their tech is compatible with existing telecommunications equipment.

In PRX Quantum, where the team published its findings, they say their work provides "a realistic foundation for a high-fidelity quantum Internet with practical devices." They added, "this is a key achievement on the way to building a technology that will redefine how we conduct global communication." Experts believe a quantum internet could revolutionize a variety of computing fields, including cryptography and search. [...] With two 13-mile networks under their belts, the Caltech and Fermilab teams plan to build a city-scale network called the Illinois Express Quantum Network in Chicago next.
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A Successful Experiment Gets Us One Step Closer To a Quantum Internet More

A Successful Experiment Gets Us One Step Closer To a Quantum Internet

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  • I'd be happy if Charter would be stay up for 30 minutes at a time without crashing
    • Exactly. How can quantum communications hope to be reliable when ordinary electrons and photons don't do the job? This will require an extraordinarily solid infrastructure, and any communications company that is willing to pay for it will be the most expensive one.

      • i'm guessing the early adopters would be financial institutions and the military
        in both cases speed trumps all else, and cost is a very distance concern.

        • The speed is the same and not important. It's the military grade security that matters. Signals that physically can't be eavesdropped or altered, and encryption that can't be broken with quantum technology because it is quantum technology.

  • just in time (Score:3)

    by Anonymouse Cowtard ( 6211666 ) on Friday December 18, 2020 @02:51AM (#60844108) Homepage
    An exciting development and should come just before SSL/TLS is broken. If not, it's back to trading with shiny shells and beads.

  • World

  • Jian Yang!!!

    Boy, do I miss that TV serie.

  • If my packet goes via a "quantum" link, does that improve the quality of my life any? I don't think so.

    If the link is secured by one of the quantum privacy schemes, how is that better than the rather effective cryptographic algorithms we use today?

    The world is already running according to the rules of quantum physics. Isolating particles so they behave more quantumly is not magic, it's just difficult however the doers of quantum doings still needs to find an application that is in some way better than what

    • The implication is that they can also eliminate the part of the transmission latency that is a function of the distance of the end points. That's gonna improve your Quake score a lot.

      • So faster than light internet? No that's a complete fantasy.

      • The implication is that they can also eliminate the part of the transmission latency that is a function of the distance of the end points.

        No they can't because to read the teleported quantum states they need additional information that is sent through classic channels, not faster than light.

        Why is this forgotten every time?

      • No. You cannot use this to transmit information faster than the speed of light. That would violate the No Communication Theorem https://en.wikipedia.org/wiki/No-communication_theorem [wikipedia.org].

      • Correct me if I am wrong, but its still limited to the speed of light, correct?

        • Re: (Score:2)

          by HiThere ( 15173 )

          You're "partially wrong". The quantum state transportation is instantaneous. In fact it's probably faster than that, being backdated to when the correlation was created. But you can't interpret it until you receive some information which comes at regular network speeds.

          • You're "partially wrong". The quantum state transportation is instantaneous. In fact it's probably faster than that, being backdated to when the correlation was created. But you can't interpret it until you receive some information which comes at regular network speeds.

            It's like a one time pad you can bring into being in two places instantaneously, but the message protected by the pad needs to travel at under the speed of light.

      • It is amazing the percentage of people that don't understand that 'quantum anything' can't transmit real time data any faster than the speed of light. Remember the entanglement 'stuff' is only instant because it ignores that it was transmitted prior to the reading of the quantum state. You still have basic principles of data transmission that at this time we can not overcome.

  • Physics question --

    My understanding is that (1) quantum states are stored in photons, or other similarly small particles.

    Further, that (2) a quantum state becomes actual, rather than potential, once it has some kind of interaction with -- just about anything. That quantum states are in some sense, "fragile."

    Further, my understanding is that, (3) if a photon travels through the air, or bounces off a wall in a fiber optic cable, -- pretty much anything other than the vacuum of space, that it's likely that th

    • The idea is that you could use this to do a form of key exchange, and that this would replace RSA in the process. This wiki page has a reasonably accessible summary of how that might work https://en.wikipedia.org/wiki/... [wikipedia.org] I think the Chinese approach of using a satellite is much more interesting since it allows for greater distances than fiber optic and doesn't require a direct connection between the communicating nodes (entangled photos can't really be run through optical repeaters) https://www.scientifi [scientificamerican.com]

      • The question is "how can you transmit quantum
        entagled photons through a fibre optic cable, when
        that cable is made of atoms that should cause the
        transmitted photon to decohere"?

  • Teleportation? (Score:4, Interesting)

    by stealth_finger ( 1809752 ) on Friday December 18, 2020 @06:21AM (#60844408)
    If you are teleporting then why do you need a cable? If they are sending something down a cable then thats not teleporting, is it?
    • You can teleport marbles the same way. Take a black and white marble, put each one in a bag without looking at them then send one of the bags via courier to a destination. Now at some point in the future the recipient can decide to open the bag, and at that point the information about the two marbles has now been teleported. Neat, huh?

      Now where's my several million dollars?

      • Re: (Score:2)

        by HiThere ( 15173 )

        Pretty much. The only difference is that the color of the marble is fixed all along, but you can't prove that the value of the quantum state was fixed until you look at it. I happen to believe that it was fixed, but then I also believe in the Wheeler multiverse...which implies that. Many other interpretations of quantum physics imply that it's uncertain until you look.

    • "Teleporting" is a quaint way of talking about quantum entanglement. Fiber is needed to send one photon elsewhere; it is not this that is called teleporting but the fact that you now have two entangled particles, one here and one there. Einstein, Podolsky and Rosen worried about this...even before today's terminology was created.
    • As I understand teleportation, it requires at least three actions:
      1. Deconstruct the object
      2. Send the deconstructed bits elsewhere
      3. Reconstruct those bits at the destination

      Without step 2, all you have done is cloned the object. So how do you propose we accomplish step 2 without a cable?

  • Okay, maybe not so simple. I have a few questions.
    Quantum encryption is most emphasized in popular media but the below popular summary on PRX Quantum is intriguing.

    1. Is there a maximum speed at which useful information can be transmitted? I am guessing it is c, except for within an entangled computation in which basically two points are in the same place informationwise. Correct?

    2. Once a quantum connection is transmitted as in the experiment, does this connection provide a layer over which a file can be sent for a limited time, in which your data does not travel over the fiber as photons but rather is communicated by reading states of one side of the pair? Or is it limited to basically "sharing a password"?

    3. The term "quantum resources" is intriguing and not so clear to a layman.. Is it implied that two quantum computers of 50 qubits in different cities could be connected such that a single 100 qubit entangled computation could be performed? or is there a physical impossibility due to noise, etc.?

    "The goal of a quantum network is to distribute qubits between different locations, a key task for quantum cryptography, distributed quantum computing, and sensing. A quantum network is expected to form part of a future quantum Internet [20–22]: a globally distributed set of quantum processors, sensors, or users thereof that are mutually connected over a network capable of allocating quantum resources (e.g., qubits and entangled states) between locations."

    • I have a quantum bridge for sale if you're interested, buy now and I'll throw in some free AI.

    • 1. The maximum transmission speed is still c. The wikipedia article on quantum teleportation is fairly straightforward on this. In order to do quantum teleportation, Alice and Bob each need one of a pair of entangled photons. In order to teleport a photon, Alice entangles it with her shared entangled one, applies some quantum gates, and makes some measurements that result in 2 classical bits. She sends those bits to Bob using a standard classical channel, who applies a different set of quantum gates to h

  • I am already using Firefox Quantum for almost all my internets

  • 90% huh (Score:1)

    by Chas ( 5144 )

    Well, I would say that level of accuraci is pretty good.

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