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Breakthrough Brings Star Trek Transporter Closer

Posted by ScuttleMonkey on from the scott-me-up-beamy dept.

japerr writes to mention The Independant is reporting that a new breakthrough may bring scientists one step closer to a Star Trek style transporter. " A team of physicists has teleported data over a distance of 89 miles from the Canary Island of La Palma to the neighbouring island of Tenerife, which is 10 times further than the previous attempt at teleportation through free space. The scientists did it by exploiting the "spooky" and virtually unfathomable field of quantum entanglement - when the state of matter rather than matter itself is sent from one place to another. Tiny packets or particles of light, photons, were used to teleport information between telescopes on the two islands. The photons did it by quantum entanglement and scientists hope it will form the basis of a way of sending encrypted data."

11 of 503 comments (clear)

  1. Einsteins view at least by jshriverWVU · · Score: 4, Informative
    Albert Einstein described quantum entanglement as "spooky action at a distance" and it relies on the fact that two photons can be created in such a way that they behave as a single object, even if they are separated by large distances. In behaving in this way they are acting as a teleportation machine because any changes to one causes similar changes to the other.

    1. Re:Einsteins view at least by TwilightSentry · · Score: 4, Informative

      IANAphysicist, but from what I know about entanglement, the idea is as follows. Particles (photons, electrons, etc.) do not have some values (eg, spin, charge, etc.) defined until they are observed. The fun happens when you have a process which is guaranteed to produce two identical particles, but does not cause the attributes of those particles to take a value. You can separate the two particles, and when one is observed, you have a guarantee that the other will take the same values, even if there hasn't technically been enough time for information to flow from one particle to the other.

      You can't actually transmit information using entanglement. (From my even more limited understanding, in quantum teleportation, the entanglement is used to extract the quantum state of an object and store it in a photon, which is then sent somewhere else using something like fiber.) You don't control the state of the particle when you first observe it; it is completely random. If you actually change one particle, the two particles are said to "decohere" and are no longer entangled.

      Again, I'm just an interested amateur, so please correct me if I'm wrong.

      --
      How to enable garbage collection on a system without protected memory: #define malloc() ((void *) rand())
  2. Re:Matter? Yeah, right. by ObjetDart · · Score: 3, Informative
    Have these guys who wrote the summary heard of the Heisenberg uncertainty principle? It was in all the papers.


    Sure they have. That's why all the Star Trek transporters employ "Heisenberg compensators". Duh.

    --
    I read Usenet for the articles.
  3. Re:Teleport? by brunascle · · Score: 4, Informative

    you missed the part about quantum entanglement, which is not simply fiber optics. Niels Bohr is rolling in his grave right now.

  4. Re:IANAP.... by lilomar · · Score: 4, Informative
    No. At least, not according to this article in the last issue of Darkermatter.

    So could these entangled particles be used for superluminal communications? To achieve this we would need to create two or more identical (or cloned) particles and then separate them physically from each other. Then if we were to act on one of the particles, an observer of the second should be able to detect an effect. Then introducing a code (such as Morse Code) would mean we should be able to communicate at greater than the speed of light.

    Such a thing is unfortunately impossible. In 1982 physicists Bill Wootters, Wojciech H. Zurek and Dennis Dieks introduced the No Cloning Theorem. This theorem states that it is impossible to create an identical copy of an arbitrary unknown quantum state. As cloning is a requirement of using these entangled particles for superluminal communication, we have to rule this method out.
    --
    The creator of this post (Jacob Smith) hereby releases it, and all of his other posts, into the public domain.
  5. Re:Teleport? by UnHolier+than+ever · · Score: 3, Informative

    It is teleportation of information, not of matter. We scientists define teleportaion as "moving something between point A and point B without ever being in between", which is different from the Star Trek "transforming matter in energy and into matter again". It does get us a whole lot more funding than if we had called it something unfashionable like "Communication through entanglement".

    By the way, IAAT (I am a teleporter). I don't get to work work in the Canaries though. It's a shame.

  6. Re:One step closer to an ansible, maybe. by moderatorrater · · Score: 3, Informative

    The ansible communicated by means of two entangled particles. That is impossible by everything that we currently know.

    The type of system they're talking about is where you use entangling to imprint the differences between two particles on a third one. They're fundamentally different and resemble neither the ansible nor star trek transporters.

  7. Re:One step closer to an ansible, maybe. by brunascle · · Score: 4, Informative

    by utilizing the properties of quantum entanglement, it may be possible to achieve faster-than-light communication
    no, it isnt. this has nothing to do with the speed of light. you cant use quantum entaglement to send data faster than light. no one is trying to.

    if you're trying to send data, you'll still need to send photons (or other particles) from one location to another. when you're talking about quantum entanglement and sending data across distances, what you're doing is taking two photons in the same location and tieing them together, then sending one of the particles across a distance. when it gets there, it's still tied together (unless something screwed it up on the way), but if you try to manipulate your photon then it unties from the other, so you cant use it to send info faster than light.
  8. Re:IANAP.... by khayman80 · · Score: 5, Informative
    Unfortunately, it's not easy to demonstrate that FTL communication implies backwards-in-time communication without using spacetime diagrams. I've done a little googling, and the best website I could find on this subject is here.

    The gist of the argument is that special relativity divides the universe into three regions of spacetime: the timelike future (which is the set of all points where you COULD be in the future if you could travel at any speed up to and including the speed of light), the timelike past (which is where all events that could POSSIBLY have an affect on you at the present reside) and "elsewhere", which is comprised of all other events. An example of an "elsewhere" event is the state of the Mars rovers RIGHT NOW. I can't possibly know that at the moment because there's about a 30 minute light travel time delay. It's important to realize that FTL communication connects you to an event in "elsewhere" in a causal manner.

    If you draw a spacetime diagram for two people, one of whom is moving very fast (at a conventional sublight speed) relative to the other, you'll find that the "elsewhere" of one observer intersects the past of the other. So using FTL communication and sublight engines to send a message to the past would work like this:

    1. Bob gets in his fancy spaceship and travels directly away from earth at 90% the speed of light. He travels for 1 year (the time and speed aren't really important, they just allow the message to be sent farther into the past).

    2. Alice, on earth, sends Bob an instantaneous message using her FTL communication device. It travels to Bob along what Alice considers to be her "line of simultaneous events" - the line in her spacetime diagram that goes through her present position and on through "elsewhere", to define the "present". It's not necessary for Alice's communication to be instantaneous, but it makes the argument (a little) clearer and doesn't really matter because going 1.0000001x the speed of light is just as impossible as going infinitely fast (as an instantaneous communication device would have to do).

    3. Bob receives the message at the exact instant (in Alice's timeframe) as when she sent it. He then sends the message back to Alice using the same FTL device. The difference is that Bob is travelling at 90% of the speed of light, so his "line of simultaneous events" is completely different- it actually intersects Alice's "timelike past".

    All of this makes a lot more sense once you get the hang of drawing spacetime diagrams, but it confused me for many years. You might want to google for tutorials on spacetime diagrams or "pole and barn" paradoxes to see some examples of spacetime diagrams...

  9. Re:Bad Summary by big_oaf · · Score: 5, Informative

    Sorry to nit, but since we are flexing our geek muscles here (the only muscles I have), Data has actually used contractions on occasion. According to Memory Alpha, "...Data also had trouble using contractions in regular speech although this was part of his programming by Dr. Soong." So apparently, it was possible for Data to use contractions, but not without difficulty and, therefore, rarity.

    --
    -- My hovercraft is full of eels.
  10. Re:One step closer to an ansible, maybe. by bh_doc · · Score: 5, Informative

    Wrong. Completely and utterly wrong. You can't send information faster than the speed of light.

    Quantum teleportation doesn't work like that. Here's basically how it works: Two quantum particles are entangled. Then they are separated from each other, one goes to point A the other to B. If you do a measurement on A and COMMUNICATE THE RESULT OF THAT MEASUREMENT to where B is. The other guy can do a special measurement on B based on what A's result was. Then the state of A becomes what the state of B was originally. The particles have not moved (the measurements have changed their states, though), but A's state has been "teleported" to B. It's all to do with the fact that the two particles were entangled in the first place.

    But the very important point is that you *still have communicate the result of the first measurement*, which means you're limited to the speed of light.

    There is still application for encryption since just knowing what the result of the measurement was is not enough without having the actual entangled particle B.

    BUT THERE IS NO APPLICATION TO STAR TREK-LIKE TELEPORTATION OR FASTER THAN LIGHT-SPEED COMMUNICATION. And frankly I'm getting tired of seeing the same wrong information getting played in the media like this. And slashdot even, come on guys, you should know better by now. I'm new here, aren't I?

    Yes, IAAQP.