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Quantum Dots Might Be Key For Teleportation

prostoalex writes "Researchers from Nanyang Technological University in Singapore have created a model teleportation system using quantum dots. PhysOrg reports that 'tiny clusters of atoms known as quantum dots may be excellent media for quantum teleportation, a physics phenomenon in which information — in the form of a quantum state, a very specific mathematical signature of an atom — can be transmitted almost instantaneously to a distant location without having to physically travel through space.'"

39 of 221 comments (clear)

  1. How much POWER will that take? by Travoltus · · Score: 2, Insightful

    Measured in nuclear reactors, I mean.

    "Teleporting one quantum dot will take 5 nuclear reactors", and such.

    --
    --- Grow a pair, liberals... stop letting the Republicans bully you!
    1. Re:How much POWER will that take? by Nullav · · Score: 2, Insightful

      Depends. Are we talking about text, page scans, or the actual Library of Congress? What do you mean by 'it'?

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      I just read Slashdot for the articles.
    2. Re:How much POWER will that take? by vertinox · · Score: 4, Funny

      It depends on what kind of nuclear reactors.

      Are we talking about Africa or European reactors? And secondly how would two reactors carry the quantum dots? With a line or a strand of creeper?

      --
      "I am the king of the Romans, and am superior to rules of grammar!"
      -Sigismund, Holy Roman Emperor (1368-1437)
    3. Re:How much POWER will that take? by ethicalBob · · Score: 3, Funny

      Obviously it would take 1.21 gigawatts

      (oh, wait... only if it's encased in a Delorean)

      --
      Politics will sooner or later make fools of everybody... - Dick Armey
    4. Re:How much POWER will that take? by Tumbleweed · · Score: 3, Funny

      The biggest difference between the gate system and Trek's teleporters is the distance involved. That and the creators.

      Whereas, the biggest difference between Star Trek and Stargate SG-1 is that Star Trek stole from westerns, and Stargate SG-1 stole from every sci-fi show that's ever been shown. (I'm not saying they did it badly, though.)

  2. Biggest Hurdle by JimboFBX · · Score: 5, Funny

    Biggest Hurdle so far is figuring out how to stop the quantum pac-man who keeps eating them.

  3. NOT a matter transporter by Cousarr · · Score: 5, Informative

    Quantum entanglement is a great way to get information from one location to another at faster than the speed of light but offers no way to transmit matter. Theoretically the precesses here allow for technology like the ansible from Card's Ender's Game series but won't be transmitting ensign Ricky to his death from aboard the starship enterprise. Now, if we were all information-based entities teleporting about using quantum entanglement would be highly feasible.

    1. Re:NOT a matter transporter by Anonymous Coward · · Score: 5, Informative

      Your post is almost rigth. Quantum entanglement is used for quantum teleportation but in no way can informaion be transmitted faster than light. In fact in order to be able to teleport somehing, some classical information has also to be exchanged.

    2. Re:NOT a matter transporter by Seumas · · Score: 5, Interesting

      First of all, I don't want a matter transporter. People are going to insist on using it for an alternate form of transportation. That might seem a fantastic idea, but just wait until some underpaid asshole with a hangover uses the wrong coordinates and doesn't beam you into your office cubicle, but sticks you halfway into a concrete wall in the lobby of your office building.

      Now, as for actual matter transportation -- and particularly people -- I've always wondered exactly how that would work. I am not one of those morons who believes that we have a soul or some particular part of our body or supposed spirit that makes us who we are. So - does that mean that simply taking my precise atomic makeup at point A and re-assimiliating it with different atoms over at point B will result in a real, actual me? Or would it be me without whatever makes me myself? I mean, soul and spirit bullshit aside, how could every neuron firing in my brain and every receptor and every blood vessel and capilary and memory stored away in my brain ever be re-produced somewhere else? Surely with so many trillions or quadrillions of atoms that make me up, there will always be some loss. So when you transport me from home to the office, I am a lossy me.

      And then, of course, the more you transport, the more you become like a photocopy of a photocopy of a photocopy of a photocopy. Or, if you like another analogy, you go from being Alec Baldwin to Stephen Baldwin to Daniel Baldwin to a pool of primordial goo.

      I've also always wondered what would keep someone from just creating many copies of themselves. A transporter would never truly transport you. It would simply map your makeup here and assemble the same thing somewhere else. But that isn't to say that you'd have to destroy the version at point A from which the map came.

      So at best, we might some day have matter duplicators. There is no way we would ever have matter *transporters*. If you are going to assemble an orange a mile away, why bother with the energy to destroy a perfectly good orange here, that the duplicate came from? And when it comes to people... can you possibly imagine the indescribable agony you would experience every time you went through the process? They'd confirm that your duplicate was assembled and functional at your destination... and then destroy you at your point of origin. You would somehow be taken apart at the atomic level. Perhaps reduced to a very fine recycleable dust. It wouldn't be harmless and fun like in Star Trek. It would probably be like having a trillion surgical scalpels cutting into you while every inch of your body inside and out felt like it was burning and being shredded and ripped apart.

    3. Re:NOT a matter transporter by asuffield · · Score: 5, Informative

      I've also always wondered what would keep someone from just creating many copies of themselves. A transporter would never truly transport you. It would simply map your makeup here and assemble the same thing somewhere else. But that isn't to say that you'd have to destroy the version at point A from which the map came.


      Various fundamental results have already been formally proved about quantum physics. One of them is the no cloning theorem, and one of its many implications is that no duplication is ever possible: copying anything on a quantum level must always involve destroying the original.

      Another proven result is the no teleportation theorem. This one indicates that quantum matter teleporters are fundamentally impossible. It just can't be done. It's not a problem with scale or accuracy, you cannot even teleport a single atom.

      These two theorems are not based on vague arguments, but on the mathematics underlying quantum physics. As such they are iron-clad.

      If either a working duplicator or teleporter is ever built, we already know that it will not be based on quantum physics, but on some lower level of physics that has not yet been discovered. This is unlikely to happen in our lifetimes (it takes roughly 100-200 years to move from one level of physics to the next, based on history).
    4. Re:NOT a matter transporter by robably · · Score: 2, Funny

      Now, if we were all information-based entities teleporting about using quantum entanglement would be highly feasible.
      We are information-based entities. You'd still be you if your mind was teleported in to another body. Maybe a robot body. With breasts.
    5. Re:NOT a matter transporter by Jamu · · Score: 3, Interesting

      I'm not so sure the teleportation theorem does say that. If it's possible to transfer quantum states without measurement, and all you need for teleportation is to transfer these states, then you don't need to make measurements (which is what the teleportation theorem describes). Quantum physics doesn't rule out teleporters. In fact, the cloning theorem suggests that if you do teleport a person, then they are teleported and not destroyed after duplication. That is, if you only transfer their state and don't make measurements in the process of teleportation.

      --
      Who ordered that?
    6. Re:NOT a matter transporter by Mudcathi · · Score: 5, Funny

      "Your post is almost rigth." Whath wongth whith ith?

      --

      "He who throws mud, loses ground." - proverb

    7. Re:NOT a matter transporter by SEWilco · · Score: 2, Informative

      The risk of cancer from DNA corruption scares the hell outta me.
      Alteration of DNA is not as disastrous to the body as you might think. The decay of a C-14 atom in DNA happens about 50 times per second, changing a carbon atom to one of nitrogen. So there is DNA corruption in about 50 of your cells each second from that cause alone. How often that has disastrous consequences for each cell is somewhat relevant to the body.
  4. Speed? by Anonymous Coward · · Score: 2, Interesting

    "Almost instantaneously" seems to be another way of saying "not instantaneously", which we could have guessed anyway. So why not say how fast it actually is?

    1. Re:Speed? by asuffield · · Score: 3, Interesting

      "Almost instantaneously" seems to be another way of saying "not instantaneously", which we could have guessed anyway. So why not say how fast it actually is?


      It's not measurable (really! to measure it would require a system that can transport information faster than light, and that's not possible so far as we know) and not really important. You teleport an entangled blob of quantum state, which arrives "almost instantaneously". You cannot do anything with it until you receive the companion classical information from the transmitter, which you need to "unpack" that blob of quantum state and extract the teleported information from it. The effective speed of the process is precisely the same as the actual speed of your classical (non-quantum) slower-than-light information channel, and that's the important part.
    2. Re:Speed? by zCyl · · Score: 2, Interesting

      "Almost instantaneously" seems to be another way of saying "not instantaneously", which we could have guessed anyway. So why not say how fast it actually is?

      Quantum teleportation requires the transmission of classical information before the "teleportation" can be completed, and the transmission of this classical information is done by conventional means which are limited to the speed of light. For some reason there seems to be a popular and often repeated misconception that quantum teleportation is instantaneous, but it is not, due to this classical information requirement.
  5. Read the discussion... by niceone · · Score: 4, Informative

    The article is pretty light on information, but hte discussion has a pretty thorough description of why this can't (AFAIK) be used to send information, including a link to the wikipedia topic. Maybe they have a way round that, but you can't tell from the article.

  6. Teleporter death by AmiMoJo · · Score: 4, Interesting

    This reminds me of a question I never found the answer to: if you teleported yourself, would you die and a clone be made?

    From the sounds of TFA, the new "you" would not actually be you at all, just a copy. It sounds like your conscious mind would be obliterated and a new one created, although the new one might not be aware of it.

    --
    const int one = 65536; (Silvermoon, Texture.cs)
    SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
    1. Re:Teleporter death by WarJolt · · Score: 5, Insightful

      What you are talking about is philosophical issue. With teleportation you no longer exists where you were and you exist where you are now, but thats true as you walk through space. I think the problem occurs when you consider the energy that makes up your matter is part of you.

      Let me ask you a question. Isn't it true that your cells are constantly regenerating themselves? The matter you were made up of when you were born no longer is the same matter, but you are still you. So if your qunatum state was duplicated and during the process the original was destroyed then you would still think you are you. Would you still BE you? That just opens a whole can of worms.

      The question in my mind is can quantum teleportation bring along your soul? If you don't believe in a soul you have to ask yourself a couple of questions. Are you only you because of that matter that makes you up? The matter that makes you up comes from the stuff you eat. So is the stuff you eat part of you before you eat it? Is it only you when you make food part of your cells and your body? What makes you unconfortable with the idea of your body being made up of different energy? Consider this: Your body is constantly rebuilding itself with new and different energy and disposing of the old parts. Whats the difference?

      I bet most people wouldn't step into a teleportation unless the quantum state of your atoms were reconstructed with the SAME energy.

    2. Re:Teleporter death by Lobais · · Score: 2, Interesting

      Exactly, because if we said that it _would_ be _you_ in the new body, then if the old you was not destroyed you would be consciously in two bodies at the same time, and that'd be rather confusing.

    3. Re:Teleporter death by stjobe · · Score: 4, Insightful

      Oh, but I disagree :)

      "Just" philosophy (as you so eloquently put it) is not at all "meaningless and essentially useless", and quite a few answers can and have been found through philosophy.

      However, the questions that are asked in philosophy cannot usually be answered empirically. Neither by observation or experiment, nor by reference to faith or revelation, but rely instead wholly on reason. This should not be taken as evidence that the questions cannot be answered. Logic, for instance, is based purely on reason and it springs, as do so many other fields of study, from philosophy. It also answers a lot of questions.

      In fact most of what we now call science was at one time or other found under the heading "philosophy", and only with advances in philosophy did it spring forward as a science in it's own right.

      So you see, far from being meaningless and essentially useless, philosophy is in fact inherently meaningful and useful as a tool to explore areas of knowledge science does not yet have the ability to tread. For instance, the philosophy of mind to which this discussion pertains.

      --
      "Total destruction the only solution" - Bob Marley
    4. Re:Teleporter death by caudron · · Score: 2, Interesting

      Let me ask you a question. Isn't it true that your cells are constantly regenerating themselves? The matter you were made up of when you were born no longer is the same matter, but you are still you. So if your qunatum state was duplicated and during the process the original was destroyed then you would still think you are you. Would you still BE you?

      I'd argue the answer is no, but it is, as you point out, an existential problem. For many people there is a qualitative difference between the slow regeneration of that which constitutes you and a transfer of the information that is your current state of being. That's slow regeneration creations a continuity of self that the latter doesn't afford. Does it matter existentially? Well, as Kierkegaard said, Truth is subjectivity. You'll need to decide that for yourself. For me, that continuity is key to selfhood.

      The question in my mind is can quantum teleportation bring along your soul?

      Agreed that this is the million dollar question, made all the more difficult because of the muddying of the term 'soul' itself in the Western world.

      In the Hebrew context of the dominant Western faiths (Judaism and it's derivatives, Christianity, and Islam) the soul is not separate of the body. There is no distinction of body and soul in the Jewish, Christian, or Islamic holy texts. The Christian resurrection is a bodily resurrection. The Islamic understanding of heaven is a physical one. The Jewish people never made that distinction. In that context, the question falls away. The soul isn't brought along in any different a manner than your liver or skin. Indeed, by virtue of bringing liver and skin over, you subsume the soul in the transfer in a very real tangible sense. In the Hebrew context, the soul is in no more danger than the body of being labeled a copy.

      In the Greek context that informs our Western philosophical outlook, and often works at odds with our religion outlook, there is very much a distinction of Mind, Body, and Soul. So, in that context, the question gets even broader in that you must also ask the same question of the mind. Is it brought over with the body? Is the soul as well? Being separate and noumenal, the mind and soul may not be brought over but copied or a new one created in the reconstitution of the copied body. In that Greek context, teleportation is existentially dangerous, I'd think.

      Personally, I've always tended to adhere to the Hebrew context for these sorts of questions, as they seem to make more logical sense and fit closer with my understanding of how the world appears to work.

      Not sure that I was coming to any conclusions in this comment, but rather just adding to the thought-noise. :)

      Tom Caudron
      http://tom.digitalelite.com/
      --
      -Tom
  7. Quantum dots by Anonymous Coward · · Score: 2, Funny

    kids have such cute names for herpes these days!

  8. Re:Cool. by Derosian · · Score: 5, Informative

    A good place to start 'understand' quantum mechanics is to see the double slit experiment. Link.

  9. Re:A little confused... by asuffield · · Score: 4, Informative

    I was under the impression that quantum entanglement could not transmit information. If these researchers have actually managed superluminal commmunication, then... wow.


    It cannot transmit information faster than the speed of light. It can transmit information when combined with a classical, slower-than-light transfer. It cannot transmit any information without having a classical (non-quantum) information transfer also take place, so the speed is limited by the speed of the classical transfer.

    As you would expect, the utility of this is somewhat limited.
  10. Couldn't time delay be the form of communication by ConfusedSelfHating · · Score: 2, Interesting

    Let us take 9 "quantum pairs" (honestly, I don't know the exact terminology of them). You have 9 of them on Earth (A) and 9 of them elsewhere (B). They are ordered from 0 to 8. Assuming that you can determine when the quantum waveform collapses into spin up or spin down, you start the communication when A0 is caused to collapse. Instantly B0 becomes up or down. That's the start of the communication. If after 1 ms, B1 is found to have collapsed into an up or down, that counts as a 0. If after 2ms, B1 is found to have collapsed into a up or down, that counts as a 1. You would be able to generate a byte of data this way.

    So start-2-1-2-1-1-1-2-1, would be 10100010.

    The point is that it doesn't matter whatever B0 to B8 end up as. Just when they end up as an up or a down.

    Are you going to be able to determine whether the waveform has collapsed without collapsing it yourself.

    Of course, I didn't sleep last night. My guess is that if you are in a position to determine whether or not the waveform has collapsed, you will collapse it yourself. Maybe there's an indirect method.

    As far as matter transportation, I wouldn't rule it out as impossible. I certainly wouldn't say it's inevitable. When quantum communication is studied in greater depth, some inconsistencies may be uncovered which could lead to a "greater truth".

  11. Re:quantum dots by suv4x4 · · Score: 2, Funny


    If these particles can actually travel faster than the speed of light...does that mean they may be from "another dimension in another 'time'" where our physical laws don't apply or being sent by other scientists doing the same experiment only in reverse from this other "place"???


    Well, thanks for confirming my original point...

  12. Faulty assumption by cat_jesus · · Score: 5, Informative

    Assuming that you can determine when the quantum waveform collapses

    This is the faulty assumption.

    Think of of entanglement this way. You have two roulette wheels and they are "entangled". What this means to the roulette wheels is that they are spinning and the marbles are bouncing along inside them synchronously(I know they'd be at right angles but being the same value works well for the visualization). So you split them up and one roulette wheel is in another galaxy and the other is here. Both are spinning and the marbles are still bouncing around in sync. If you stop one, the other keeps going. If you stop them at the same time the marbles will have the same value. But the problem is the one you assume away. You cannot tell that the other roulette wheel has stopped.

    In QE, if you attempt to observe the entanglement, you make it collapse. You can't tell what the state of the particle is without destroying the entanglement.

    IINAQP and I could be wrong. But this is my understanding and my cousin who is a Physicist tells me I have an accurate, if rudimentary, understanding of this particular phenomenon.

    I wish you were right.

  13. Re:bullshit by afaik_ianal · · Score: 2, Interesting

    I don't know that the Offtopic mod was all that fair on this post. Sure, it lacked a little detail, but what's with this "almost instantaneously" bullshit that keeps coming up every time we talk about teleportation?

    Maybe it's plausible in a Star Trek universe, but in our universe, we appear to be constrained by the speed of light, even for transmitting information through entanglement. Sure, one might argue that speed of light is instantaneous, but we all know that this kind of language gets a bunch of readers' hopes up every time.

  14. It won't work for communication... by Jafafa+Hots · · Score: 2, Funny

    At least not until we figure out how to use quantum DASHES along with the quantum dots.

    --
    This space available.
  15. Re:Cool. by Davey+McDave · · Score: 3, Informative

    That's basically quantum computing for you. You can get them involved in such a state that they can influence one another even though they're not even next to one another (action at a distance). Hence they're sort of invisibly entangled within one another, if you mess around with one the other will instantly change. This is pretty great though, because if you can get all these things to represent a calculation, and act upon it, it instantly changes at this other place you can read them. Even better, if someone else tries to read it at the other place it'll show up back at the origin.

    Quantum isn't really a buzzword, it actually means that it's taking advantage of the fact that energy is discrete rather than continuous. It's supposed to be used in opposition to classical or Newtonian mechanics, which assumes that energy is continuous, and has a huge amount of crazy consequences.

    If you're REALLY interested in learning about quantum mechanics I'll one up the sister post and recommend you some of Feynman's lectures. In the first video here he whips through almost the entire history of physics and why QM is different: http://www.vega.org.uk/video/subseries/8

    --
    I've got the spirit, lose the feeling.
  16. Re:Cool. by Rallion · · Score: 4, Funny

    And, I've found, a good place to stop understanding quantum mechanics is looking into more advanced variations of the experiment.

  17. Model teleportation system by SEWilco · · Score: 2, Funny

    They made a model teleportation system. Why do models get special treatment? I can undestand their being able to deduct makeup as a business expense, but why do they get a teleportation system first?

  18. At last... by revengebomber · · Score: 2, Funny

    Easy suicide!

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    09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
    45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
  19. Re:bullshit by civilizedINTENSITY · · Score: 2, Interesting

    "...but what's with this "almost instantaneously" bullshit that keeps coming up every time we talk about teleportation?"

    I think the confusion perhaps relates to the difference between quantum tunneling (where "almost instantaneous" shows up) and any attempt to use quantum tunneling for the purposes of information transfer.

  20. Re:bullshit by NinjaTariq · · Score: 2, Insightful

    Wasn't that was one of the problems einstein had and could never get to the bottom of was the spooky action at distance? Where effects of quantum entanglement do travel faster than the speed of light. Various theories have come along to explain it, including faster than light particles which travel between the two entangled particles effectively going back in time and setting the observed property when the two were in close proximity.

    In theory it is possible to travel faster than light, the theory of relativity is symetrical around the speed of light. But it is impossible for any particle to go across the light barrier, either slow down under it or speed up over it.

    It may be impossible to implement (currently) like many things in theoretical physics, but so were so many things we take for granted now a century ago.

  21. Re:bullshit by civilizedINTENSITY · · Score: 2, Interesting

    "The Berkeley group:

    An experiment of theirs, where a single photon tunnelled through a barrier and its tunneling speed (not a signal speed!) was 1.7 times light speed, is described in

    * Steinberg, A.M., Kwiat, P.G. & R.Y. Chiao 1993: "Measurement of the Single-Photon Tunneling Time" in Physical Review Letter 71, S. 708--711 "

  22. Re:bullshit by Torvaun · · Score: 2, Insightful

    Teleportation is absurd -now-. 150 years ago, magic picture boxes were absurd. 150 years before that, a magic box that could transmit sound near instantaneously from place to place was absurd. How about taking someone's heart out, putting a new one in, and having that person not die from it? Allowing blacks and women to vote? The very concept of a man controlling billions of dollars? The only true absurdity to be found is the certainty that things will always be as they are.

    Some of our routine surgeries would have been called vivisection. Many of our standard technologies would be called witchcraft. And when the rules said no to cruel and unusual punishment, that meant that we wouldn't be burned at the stake.

    --
    I see your informative link, and raise you a pithy comment.