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Science Technology

Laser Beam Teleported 540

Michael Wardle writes "ABC Australia reports that a team of scientists from the Australian National University have successfully teleported a laser beam. It seems that teleportation of solid bodies is still a way off, but at least we're a little closer to Slashdot's favorite super power." Another Australian newspaper has a more detailed story.
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Laser Beam Teleported

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  • by Wire Tap ( 61370 ) <frisina AT atlanticbb DOT net> on Sunday June 16, 2002 @09:03PM (#3712952)
    It seems to me, that there is a huge difference:


    Team leader Dr Ping Koy Lam says it involved creating a laser beam, its disembodiment and the recreation of the original beam in a different location.


    To me, that sentence can be translated as such:

    Team leader Ping Koy Lam says it involved creating a ball point pen, its destruction and the recreation of the same ball point pen using a factory blueprint in a different location.

    This isn't the first time I've read about "teleportation" of some particle or another, when it seems that they are simply re-creating, mirroring if you will, the particle(s) quantum states in another place. That's not teleporting - that's mimicing.
    • so you're saying it's a replicator? COOL.
      • it's not a replicator. the original object has to be destroyed for that very reason. in quantum mechanics there's a very simple to prove theorem, the so called [about.com]
        no-cloning theorem, that states that a quantum state cannot be copied without destroying the original.

        of course, if you are only interested in an imperfect copy (i.e. a copy, not the same(tm) object) of your laser carrying your information, you just take a high bandwidth detector, two lasers and modulate them with the signal from the detector.
    • by Kafka_Canada ( 106443 ) on Sunday June 16, 2002 @10:02PM (#3713204)
      This isn't the first time I've read about "teleportation" of some particle or another, when it seems that they are simply re-creating, mirroring if you will, the particle(s) quantum states in another place. That's not teleporting - that's mimicing.

      You've said the same thing in two different ways; really, there is no difference.

      But first, an analogy :P .. Some people describe me as an unmarried man, but others say I'm more of a bachelor.

      To teleport something (you can call it mimicry, or mirroring, or whatever you want -- this isn't primarily an argument about semantics) is to encode the thing's physical information (mass and topography and other stuff for matter, a somewhat different list for photons, whatever), transmit those data to another geographic location, and re-convert that info into the original object, with all the same parameters except for location.

      Now, whether you describe that as destruction-recreation (sort of like modulation-demodulation?) or teleportation, do you see that it's the exact same act? As I said before, it's not about wording: it's not about the difference in meaning (or nuances of meaning) between one word and another, but about the general meaning of "what it is to teleport a thing." If you don't understand "teleporting" to mean destroy-send-create, then how do you propose to go about it?

      Another poster replied beneath the parent thread, illustrating the popular conception of teleportation as "beam me up scotty." It's a quite apt description, but there's a part of the explanation missing. How does the "beam me up scotty" thing actually work? What can Scotty be doing that's different (in more than name) from what the physicists in Australia did, viz. destroy-send-create, a.k.a. teleport?

      Finally, about the physics itself (though superficially, of course!). From what we know now, "the way" to teleport a thing is by quantum re-creation. A lot of tricky engineering, and still a bit of a disappointment compared to sci-fi. Similarly, the physics of real-life time travel don't seem to match the more elegant descriptions of sci-fi, and have limitations that make it seem like less than you'd expect from a subject like "Laser Beam Teleported" or "Scientists Discover Time-Travel," but it's essentially a germinal version of the same phenomenon.

      (As a side-note, this has some bearing on another popular /. topic: cloning. If you get rid of the "destroy" phase of teleportation, you've got physical cloning, which in some ways is considerably nicer than biological cloning... and with, of course, correspondingly higher ramifications of abuse!)

      • Actually, this situation precisely corresponds to one of my old favourite what-if questions. It shortly turns into: Does a human have a soul (or indeed any other unknown and intangible unique quality)?

        If not, then a quantum copy is the same being. Correctly done, the 'original' is destroyed, the 'copy' goes on, last memory being at the other place. No harm, no foul. Murder? Who can tell?

        If you're not allowed to 'destroy' the original, what happens if you want to reintegrate quantum state (mostly memories, but there are quite a few other interesting possibilities, such as the usual with cloning - if the original dies, can the copy be considered the posessor of the identity? Is the copy even considered human? etc)

        At what point does the HIAU (Human Industry Association of the Universe) step in and penalize you for a copyright violation? Or are you allowed one backup copy for personal use?

        Does the human being already have copy-protection built in, or not?
      • by sacrilicious ( 316896 ) <qbgfynfu.opt@recursor.net> on Monday June 17, 2002 @08:29AM (#3714765) Homepage
        Now, whether you describe that as destruction-recreation (sort of like modulation-demodulation?) or teleportation, do you see that it's the exact same act?

        I think the key issue that isn't being articulated here is that destruction-recreation can only be easily thought of as teleportation if the destruction phase is an absolutely necessary, intrinsic part of the process. Otherwise, what you've got is a situation where something is duplicated, and the only reason to destroy the original is to preserve the metaphor of teleportation. In the case of teleporting humans, unnecessary destruction comes uncomfortably close to, well, murder. It is for this reason that people (rightly so) feel the need to draw a clear line between duplicative technologies and transportive technologies.

        An evocative scenario involving this conundrum is a "teleportive" technology used on people in which the original has to be destroyed because of technological limitations (incomplete knowledge or deviation of lab results from theory), instead of because of a demonstrable theoretical limitation (like Heisenberg's principle as the foundation of quantum encryption). What if people embrace and use such a technology as "teleportive" for ten years, then technology improves and we suddenly don't need to destroy the original? Whether the use of teleportation would come to a grinding halt or people would continue (now unnecessarily) to destroy the original would be very interesting indeed.

    • "What we have demonstrated here is that we can take billions of photons, destroy them simultaneously, and then recreate them in another place," Dr Lam told The Australian.

      This also involves entanglement. The photons get re-created almost instaneoulsy. This nothing like sending the blue-print for pen to a factory. This is sending the information for a 'pen' to a device the re-creates the 'pen' from raw atoms instantly - just like Star Trek. Of course they are just using photons which simplifies things as they are all 'the same' and massless.

    • by jacobb ( 93907 ) on Sunday June 16, 2002 @11:03PM (#3713417) Homepage
      In quantum mechanics, no particle can ever be said to "exist," per se. Thus the quantum universe is made up of "probability fields" much like the electron clouds from highschool chemistry. In essence, (IANAQM ["quantum mechanist"]) each quantum (singular of quanta) has a probability cone relating to it's predicted position and speed. I believe in theory, particles can "wink out" or "blink in" (of existence that is), though the probability is exceedingly low.

      This brings up the point of How do you define "teleportation"?
      if creating a photon from an identical ('quantumly') photon in another place, so long as the original is necessarily destroyed (and this is the only possible case) and you have duplicated ALL attributes: phase, amplitude, polarization as well as all quantum attributes (of which i know little) then you HAVE teleported it! Unless you give photons some kind of aethereal, disembodied "essence" or "soul" that is by definition an unique and induplicable attribute, then i fail to understand your disagreement with the moniker "teleportation". And entanglement makes this all work out kind of nicely.

      If you want some more info that's easy to read, but very informative about quantum teleportation and entanglement, see this excellent summary [ibm.com]
      In writing this reply, i tried to include a summary of that article, but it's pretty impossible to summarize. I would have had to copy,paste huge paragraphs - they give you no more info than really necessary while keeping it very interesting. READ IT!

      Discussion welcome!! Mods: please don't 'OT' thread below. knowing me, it could get obscure/wierd/esoteric - almost certainly offtopic, though. at least eventually.. pretty please? :-P

    • This isn't the first time I've read about "teleportation" of some particle or another, when it seems that they are simply re-creating, mirroring if you will, the particle(s) quantum states in another place. That's not teleporting - that's mimicing.

      I'm not sure what you think the difference is. However the important point to the story is that the team used quantum entanglement to transfer the information. That's amazing stuff in itself. It's going to change communications even if it doesn't lead to Star Trek teleporation devices.

  • But isn't this simply the assembly and dissembly of a beam of a certain protocol. Once we can find the algorithm to define the structure of solid objects, it shouldn't be that hard. (Ask Stephen Wolfram... he'd seem to agree in his new book.) This isn't TRUE teleportation... just the appearance of such a phenomenon. Let's not jump to conclusions.
    • wierder conclusion (Score:4, Insightful)

      by BlueboyX ( 322884 ) on Sunday June 16, 2002 @10:43PM (#3713349)
      The jump to calling this teleporation isn't that bad. This is kind of a teleporation of information (physical state of the photons), but it isn't true teleportation in that matter that was here is now over there.

      What I think is an even wierder conclusion to jump to is the claim that this will make supercomputers the likes of which we never have seen, as much faster than current computers as current computers are faster than pre-transister computers. Now where does that come from? We are reaching a point where the size of silicon chips is causing problems, so magically teleporting info from one side of the chip to the other instantly would be a big help. But I wonder at the kind of hardware that would take, and the conversion process. Can this route the info the wherever it is needed in realtime, or is there a delay as data is chopped up into chunks that the data teleporter can handle? It wouldn't take much of a delay to totally negate any benefit from doing this for cpus of current size. It would have to be like a foot long cpu to be any good if that was the case! :P All that may not be the case; it depends on the specifics of how this process works, which is not given in sufficient detail in the articles.

      Basically, I am making the same argument as I made against how (normal, non-teleported) light based computations will replace current electron based computations. It would have to be a 100% photon system because if you have any kind of conversion involved, you are going to slow things down, ruining the point of using photons to begin with.

      Yeah, I can see how really, really advanced technology beyond anything currently made in research labs could possably overcome all these problems, but I don't see any of that happening in my lifetime.

      It is nice to dream, but dont take bets on when photon circuits and teleporation cpus replace silicon. :>
  • by yog ( 19073 ) on Sunday June 16, 2002 @09:07PM (#3712974) Homepage Journal
    Suppose they get this working with matter. Then it's just a matter of time before humans would walk into a chamber and be rematerialized somewhere else. The question is, who walks out of the destination chamber? Is it me or is it a reconstructed "me" with a different awareness, while the original "me" was destroyed? Even if it's a perfect copy, it's not worth the risk.

  • by Wrexen ( 151642 ) on Sunday June 16, 2002 @09:13PM (#3713013) Homepage
    Team leader Dr Ping Koy Lam says it involved creating a laser beam, its disembodiment and the recreation of the original beam in a different location

    The team was understood to be using a device known to insiders as a "video camera", although how it functions exactly was not disclosed during their press release
  • Team leader Dr Ping Koy Lam says it involved creating a laser beam, its disembodiment and the recreation of the original beam in a different location.
    Disembodiment? Well, if that's the way a human teleport would work, you can be assured I won't be telling Scottie to beam me up!
  • How is this different from "teleporting" a sound wave by using a microphone and a speaker?
    • This is compleetly different from transporting sound by using a microphone and speaker.
      1 these are billions of photons, not the average of air preasure over the cone of a microphone.
      2 They are the teleportation makes an "exact" replica of the photons in the lazer at the other point.
      3 these are photons not waves, if you remember your high school physics light waves and light photons are two different (interconected) things.

      5 in mic -> speaker you are basicly making an electrical aproximation to the air preasure waves, sending that electrical signal down a wire, and the speaker aproximating movement of its cone via the magnetic interactions from that signal.
      In quantum teleportation such as this, the quantum states of the molecules at each end are directly conected.

      6 im sure someone eles could give a better explanation and more reasons
  • Nonsense (Score:2, Insightful)

    by Bushipunk ( 149985 )
    Quantum entanglement isn't nonsense, and I don't imagine that this teleportation experiment necessarily is either, but the article on The Australian site certainly seems to be. Am I the only one who found it to be incredibly poorly written? I'm somewhat familiar with the principles involved, but I couldn't make heads or tails of most of it.

    More detailed my foot - it was gibberish. There were definite erorrs (a previous post already pointed out that the "spooky interactions" are instantaneous, not "at the speed of light"). It's a real shame, too - this may be near-sci-fi technology, but it really isn't so arcane that a little basic proof-reading couldn't be done on articles about it.
  • by aozilla ( 133143 ) on Sunday June 16, 2002 @10:12PM (#3713248) Homepage
    As any teleportation device could clearly be used to replicate 'N Sync CDs, its use will be obviously be prohibited by the DMCA.
  • The blueprint analogy shows a lack of understanding of entanglement. There is no blueprint at the receiving end, and no measurement and communication of instructions to replicate the properties of the sending photon. What happens is a seemingly spontaneous change in the properties of the receiving photon.

    Whether this is teleportation or replication is more of a philosophical question, or maybe a matter of semantics. Is an object (or a laser beam) equal to the sum of its properties? If you can make the sum total of an object's quantum properties disappear from one place and reappear in another place, have you merely copied the object or have you moved it?

    I think you've moved it, but questions like these deserve more than offhanded answers.
    • If they can make it really long-range, as long as they can make it consume less power, it'll at least be useful for things like replacing undersea fiberoptic cables, and communication links to (at least) geosync satellites.

      It would be even better if it didn't have propagation time but hell, I'll settle for the speed at which a laser normally travels through a fiberoptic cable. That wouldn't disappoint me at all.

  • ABC Australia reports that a team of scientists from the Australian National University have successfully teleported a laser beam.

    And with this ... nobody knows where the laser beam went to.

    It is surmised that it is currently in time-space next to the time-machine that was invented several years ago, switched on ... and summarily disappeared.

  • *STAR TREK* (Score:2, Funny)

    by WetCat ( 558132 )
    **Enterprize is caught in a long range tractor beam
    ***HACK HACK HACK CHOKE!
    Kirk: Rauh! Rauh!

    May be we'll create long range tractor beams from the teleporting laser beams?
  • by NewtonsLaw ( 409638 ) on Sunday June 16, 2002 @11:13PM (#3713442)
    The article says:

    Using a process known as quantum entanglement, the researchers, led by 34-year-old physicist Ping Koy Lam, have disassembled a laser at one end of an optical communications system and recreated a replica a metre away

    and

    But the radio signal survives and is sent electronically to a receiving station, where within a nanosecond an exact replica of the beam - with the radio signal intact - is retrieved and decoded.

    I'm having trouble working out whether that nano-second is the elapsed time from when the original beam is destroyed and the new one is created, or whether it's the amount of time required to recreate the beam from the received radio signal.

    If it's the former then we're talking faster-than-light teleportation here because it takes light 3 nanoseconds to travel a yard.
  • by Mulletproof ( 513805 ) on Sunday June 16, 2002 @11:16PM (#3713449) Homepage Journal
    "An encoded radio signal is embedded on an input laser, which is combined with entanglement and then scanned. The laser is destroyed in the process. But the radio signal survives and is sent electronically to a receiving station, where within a nanosecond an exact replica of the beam - with the radio signal intact - is retrieved and decoded."

    First, a simplified definition from my very limited research into Quantum Entanglement: The supposed link between particles that have once interacted, enabling them to influence each other instantaneously over indefinite distances.

    I'll mention before hand I'm not a quantum physics major of any sort, but if I'm reading this correctly, they have encoded a laser beam with a radio signal and "quantum entangled" the two mediums which is then "scanned" (whatever the hell that is) in which the laser is destroyed in the process. So now we should supposively have an intact radio signal with a "destroyed" laser sub-atomically anchored to it in ether somewhere. Sending this radio signal downrange to a receiver will recreate this signal and "pull" the laser back into reality (pardon my butchering of terms).

    My problem here is perhapse not how unbelieveable this sound, but how damn vague the artical is. Scanning? How the hell was the beam recreated? Did it appear from thin air? Did it have to be "un" entangled? It doesn't seem as if the laser is infact destroyed at all... How do you go about "entangling" something to being with? This artical doesn't simply bog you down in scientific explanation; In fact it doesn't bog you down in ANY explanation for that matter-- it throws some words in and stirs them up with teleportation references. Hell, the only way I could figure out ANY details was independent research, and oh, how fun that was. The above definition was as easy as it got. After that? Whew... Maybe I'm just bitching, but I'm asssuming this article was written for the common man, but goes far beyond watering things down. It leaves out key pieces nessisary for understanding to occure. Jeez, that's shitty writing...
  • The point of quantum teleportation is that it preserves the quantum entanglements of the object being teleported.

    But for teleporting humans, what matters is first of all the classical physical structure: the DNA sequence, arrangement of membranes, intracellular locations of proteins, and all that. There is no indication that you need quantum mechanical information or even dynamical information in order to make teleportation work.

    Maybe it will be quantum mechanical tricks that ultimately make teleportation feasible. But these results so far really have nothing to do with the teleportation of real-world objects, because they don't solve the hard problem. The hard part is not transmitting entanglements, the hard part is transmitting the instantaneous locations of molecules in 200 pounds of matter and recreate them at the other end nearly instantaneously.

  • by NetRanger ( 5584 ) on Sunday June 16, 2002 @11:28PM (#3713492) Homepage
    I have a great idea for a device which will employ this new technology...

    How about a device that will teleport the laser back into the eye of the dumbass teenager shooting his laser pointer on the movie theater screen?
  • it's so funny ... the original transporter on star trek was introduced because they lacked the budget to handle shuttlecraft scenes. the famous roddenberry quote is "what if they just appeared there?"

    and here it is, inspiring cool science. neat.

    -- p
  • by tm2b ( 42473 ) on Sunday June 16, 2002 @11:58PM (#3713601) Journal
    My big question would be what the "speed" of the information propogation was. Some say it should be c, some say it should be "instantaneous" - either way, the results will have substantial impact on our view of several well accepted physical models.
  • Sorry, another post on the main, but there are applications far beyond encryption... Try non-line of sight laser bombardment. Still, they never mentioned what it took to re-create the laser anyway. And that's assuming this isn't just cold fusion or Internet though your AC outlet...
  • by JimPooley ( 150814 ) on Monday June 17, 2002 @04:29AM (#3714201) Homepage
    I teleported home one night,
    With Ron and Sid and Meg.
    Ron stole Meggie's heart away,
    And I got Sidney's leg.

FORTRAN is not a flower but a weed -- it is hardy, occasionally blooms, and grows in every computer. -- A.J. Perlis

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