Quantum Teleportation Sends Information 143 Kilometers

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Quantum Teleportation Sends Information 143 Kilometers

Posted by timothy on Thursday September 6, 2012 @01:28AM from the like-a-coal-mine-in-the-canaries dept.

SchrodingerZ writes "Scientists from around the world have collaborated to achieve quantum teleportation over 143 kilometers in free space. Quantum information was sent between the Canary Islands of La Palma and Tenerife. Quantum teleportation is not how it is made out in Star Trek, though. Instead of sending an object (in this case a photon) from one location to another; the information of its quantum state is sent, making a photon on the other end look identical to the original. 'Teleportation across 143 kilometres is a crucial milestone in this research, since that is roughly the minimum distance between the ground and orbiting satellites.' It is the hope of the research team that this experiment will lead to commercial use of quantum teleportation to interact with satellites and ground stations. This will increase the efficiency of satellite communication and help with the expansion of quantum internet usage. The full paper on the experiment can be found [note: abstract only, full article paywalled] in the journal Nature."

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If I recall..... by Sparticus789 · 2012-09-06 01:31 · Score: 2, Insightful

Isn't this how the Ansible from Ender's Game works? Two particles made to be in the exact same state, despite being physically separated? Too bad we couldn't have put this type of technology on Voyager 1 and 2.

--
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1. Re:If I recall..... by Anonymous Coward · 2012-09-06 01:37 · Score: 5, Informative
  
  No. No it wouldn't. Quantum entanglement does not allow for faster than light communication. Common myth.
  -- MyLongNickName
2. Re:If I recall..... by Anonymous Coward · 2012-09-06 01:51 · Score: 5, Informative
  
  But it has been mathematically proven that quantum teleportation does not allow faster than light communication. So unless you are not willing to believe mathematical proof, you should believe the previous poster's comment
3. Re:If I recall..... by Air-conditioned+cowh · 2012-09-06 01:52 · Score: 2
  
  No. No it wouldn't. Quantum entanglement does not allow for faster than light communication. Common myth.
  -- MyLongNickName
  Then what are these guys saying?
4. Re:If I recall..... by ciderbrew · 2012-09-06 01:58 · Score: 4, Funny
  
  Got a wiki page. It may well be the worst layman's explanation ever :) they got "no-communication" of that theorem just right.
  http://en.wikipedia.org/wiki/No-communication_theorem
5. Re:If I recall..... by wiggles · 2012-09-06 02:07 · Score: 5, Informative
  
  I've been watching this NOVA series on quantum mechanics - it's been an excellent primer on this stuff for me. It's hosted by Brian Greene, a prof at Columbia who wrote a book about it for a lay audience. I think it would be very approachable for anybody with an interest in science, but without a scientific background.
6. Re:If I recall..... by Anonymous Coward · 2012-09-06 02:09 · Score: 5, Insightful
  
  In the book the The Muppets, they show that frogs can talk and that pigs sometimes become infatuated with them.
7. Re:If I recall..... by MyLongNickName · 2012-09-06 02:09 · Score: 4, Informative
  
  I was the AC who posted the first reply. Please read here for more info on why quantum entanglement does not imply FTL communication. http://curious.astro.cornell.edu/question.php?number=612
  
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8. Re:If I recall..... by wiggles · 2012-09-06 02:10 · Score: 4, Informative
  
  One more thing (dammit Slashdot! Let me edit my damned posts already!!!) --
  They just did a new series (the one I linked to above is a little dated - almost 10 years old at this point). You can see that one here. It covers cosmology as well as a bit of quantum mechanics. Still very approachable.
9. Re:If I recall..... by MyLongNickName · 2012-09-06 02:13 · Score: 4, Informative
  
  Essentially, the "sender" does not get to choose the message. The sender "observes" the state of a particle with a previously undetermined state. Upon observing the particle, the "sender" causes the particle to have a determined state but does not get to determine what state that paticle is in. The "receivers" particle then has the same state as the "sender's" particle.
  So the "sender" doesn't get to choose what message he sends. He simply discovers (bad term, but trying to keep it simple) the state of the particle which becomes the same as what the "receiver" gets. This would not be useful for sending any type of communication.
  
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10. Re:If I recall..... by tnk1 · 2012-09-06 02:14 · Score: 4, Informative
  
  The Higgs was not a common myth. It was entirely expected to be there. That's a reason they spent a bazillion dollars on the Large Hadron Collider, because they expected it to be there. Yes, it was possible it wasn't there, but it fit the standard model and so it was like saying, the world could always end tomorrow, but there's no convincing reason to believe it won't be there when the sun comes up.
  Quantum teleportation does not transmit information faster than light and it is not expected to. If there was a mechanism that could do that, it would probably get its own article... and a Nobel Prize for whoever figured it out.
11. Re:If I recall..... by Anonymous Coward · 2012-09-06 02:15 · Score: 3, Insightful
  
  quantum teleportation is a understood and predicted part of physics. Of course our model could be wrong. but if something allowed for FTL information exchange, it wouldn't be quantum teleportation. I guess it would be called something else (and would invalidate most of what we know about physics, but that is another point). Prefixing every comment in a physics article with "If our current understanding of physics is correct" seems pedantic to me, but if it helps you,, maybe you should start doing that.
12. Re:If I recall..... by binarylarry · 2012-09-06 02:16 · Score: 4, Funny
  
  It doesn't, that's why you need Scotty to build you a quantum singularity, which allows you to engage the warp nacelles and initiate FTL by sling shotting the message around venus.
  Seriously, read a book or something.
  
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13. Re:If I recall..... by MyLongNickName · 2012-09-06 02:18 · Score: 2
  
  Are you seriously using a work of fiction where they made a fictional math equation to say that a real equation is wrong? Seriously?
  And honestly, it isn't even a math equation that shows that quantum entanglement does not allow for FTL communication. The sender doesn't get to choose a message, only determine a state of a particle. No data is gained by determining the state of the particle, thus no information is beind transferred. The only people claiming that this results in FTL communication are those who don't have a basic understanding of what quantum entanglement is. They fill in the gaps with what they think they know and then claim to have figured something out that physicists working on things like this their whole lives simply overlooked.
  
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14. Re:If I recall..... by locofungus · 2012-09-06 02:19 · Score: 4, Interesting
  
  I'll try.
  If two events are "time like" then one event occurs before the other *in*all*reference*frames*. i.e. the earlier event could cause the later event. Note that being time like doesn't require the two events to be causally linked but if A causes B then events A and B will be time like
  If two events are "space like" then they cannot be causally linked because it is impossible for a signal traveling at the speed of light to get from the first event to the second event in the available time. It also turns out that for space like events different inertial observers don't even agree on which event occurred first. But this causes no problems because events C and D are not causally linked.
  If an observer can travel faster than light then the above no longer holds. An observer traveling faster than light will no longer necessarily agree that A happens before B even if A causes B. An appropriate observer can wait for B to happen and then stop A from happening even though it was A that caused B. It is this paradox that leads physicists to assume that faster than light communication is impossible.
  The idea of a maximum speed isn't really that crazy anyway. There are only two possible universes, one where there is a maximum speed - which implied time dilation and everything else we see in special relativity - and one where there is no maximum speed - which you get if you take the limit as c approaches infinity in the special relativity equations and turns out to be the newtonian universe. If there is no maximum speed then there is universal time and therefore all events can be uniquely assigned a time and all observers will agree on the ordering.
  Tim.
  
  --
  God said, "div D = rho, div B = 0, curl E = -@B/@t, curl H = J + @D/@t," and there was light.
15. Re:If I recall..... by Normal_Deviate · 2012-09-06 02:21 · Score: 2
  
  I always ask this, and never get an answer. A quantum wavefunction can interfere with itself (E.g., you get interference fringes if you do the 2-slit experiment with a single photon.) But if the wavefunction is collapsed (E.g., by measuring which slit the photon goes through) then it cannot self-interfere. (The fringes disappear.)
  
  Now the punchline. The whole point of quantum teleportation is that collapsing a particle's wavefunction will also collapse the wavefunction of a remote, entangled particle. Will that destroy the remote particle's self-interference fringes? If so, then we have our ansible.
16. Re:If I recall..... by Greyfox · 2012-09-06 02:23 · Score: 3, Funny
  
  No! Quantum entanglement is more like herpes! Lets say I give you herpes! Now we share the herpes state. Later on the next person you want to have sex with checks and sees you have the herpes state. They can therefore logically infer that I also have herpes, since you claim you didn't have herpes before and I was the only person you can in contact with in between. They can arrive at this conclusion no matter where in the world I am.
  Quantum teleportation is like me calling you on the phone and giving you herpes that way. There still has to be some contact, but in this case it's phone herpes.
  So while Voyager could still use this technology to communicate, it would still have to make that phone call and wait 17 hours for the light to travel to Earth.
  
  --
  I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
17. Re:If I recall..... by Smidge204 · 2012-09-06 02:24 · Score: 2
  
  The Higgs was never a myth. It was a prediction of the standard model that, until recently, was never seen. (One could argue that they still have not put the final nail in that coffin, though). Key word: predicted. The math said it was going to be there, but nobody had managed to reach those energy levels until the last few years.
  100 years ago I doubt anyone had any opinions on quantum entanglement, which research on didn't start until the 1930s... a but shy of 100 years ago.
  So in summary, nothing in the collective theories of physics in the past century has yet been truly broken. That includes faster-than-light communication, which this would not accomplish.
  =Smidge=
18. Re:If I recall..... by Anonymous Coward · 2012-09-06 02:36 · Score: 2, Funny
  
  Remote receiver: I wonder if I have a q-mail. Let me just check if the wavefunction has collapsed yet. Oh wait, I just measured it so it collapsed. QED.
19. Re:If I recall..... by Anonymous Coward · 2012-09-06 02:43 · Score: 2, Interesting
  
  There is some dispute on this. What you say is assumed to be true but has not been proven in any conclusive manner yet and the "why" of it isn't understood. We have a general theory that says the speed of light is the speed limit for everything in the universe and given that we assume this to be true we apply that reasoning to information communicated through quantum entanglement and use the idea of the uncertainty principle to support it. That said it's all assumptions and theories at this point so to better state your response....
  No it PROBABLY wouldn't. We don't understand it completely but quantum entanglement is not believed to allow for faster than light communication.
20. Re:If I recall..... by beelsebob · 2012-09-06 02:50 · Score: 4, Interesting
  
  It's mathematically proven that if our current understanding of quantum mechanics is correct that quantum teleportation does not allow faster than light communication. That's not the quite the same thing.
21. Re:If I recall..... by Dishevel · 2012-09-06 02:57 · Score: 2
  
  Are you suggesting that real ones don't make mistakes like that?
  
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22. Re:If I recall..... by 0x537461746943 · 2012-09-06 03:14 · Score: 2
  
  Taking it to a simple level...
  
  You take 2 pieces of paper. Mark one as A and mark the second as B. Without looking at them you randomly put each into an envelope and send one to a remote location. You both open them at the same time and know that the other person has the opposite paper. The remote envelope had to travel by normal means. It was not teleported anywhere. The travel time is how long it took for you to send the envelope to the remote location.
  
  They really should rename this to quantum encoding or something along those lines.
23. Re:If I recall..... by mounthood · 2012-09-06 03:31 · Score: 2
  
  This would not be useful for sending any type of communication.
  Then whats the practical significance of this? Is it just the secrecy/security during transmission? The Wikipedia page also says 2 'classical' bits would have to be transmitted through a 'classical' way, which seems to remove any advantage of speed or bandwidth.
  
  --
  tomorrow who's gonna fuss
24. Re:If I recall..... by Anonymous Coward · 2012-09-06 03:36 · Score: 2, Insightful
  
  A lot of very smart people have looked over this proof carefully, since it has such profound consequences. If you have a specific criticism of the proof, present it. Otherwise you should equally well consider the possibility that Venus does not exist, since all the scientists observing it through their telescopes might have collectively made a mistake. Blind skepticism is no better than blind faith.
25. Re:If I recall..... by Kilobug · 2012-09-06 03:43 · Score: 3, Informative
  
  You can't "send states" either. You measure on your own photon (or electron, or whatever) and if you find a value. The other guy measure his own photon (or whatever) and find a value. The two values, once you communicate with each other (slower than light) will always match (be the same, or be opposite, depending of the way you entangled them). But you don't send the value of your measurement, and you don't even send the fact you did a measurement.
  It has uses, for example in cryptography. Or if you want to run a solar system wide lottery and have the people on Mars and Earth follow, exactly at the same time (warning: that's layman speach, it doesn't have any real meaning in GR), the outcome of the lottery, and no one having the result before the other. But not for communication.
26. Re:If I recall..... by MozeeToby · 2012-09-06 04:01 · Score: 2
  
  I have a choice, I believe in a world where FTL communication/travel is possible or I can believe in a world where causality holds. Even without all the math that says FTL is impossible, I'd still chose causality over FTL.
27. Re:If I recall..... by michelcolman · 2012-09-06 04:05 · Score: 2
  
  This would not be useful for sending any type of communication.
  Yes it would: it would be very useful for encrypting communication. The message itself still travels at the speed of light, but the encryption key can be chosen using quantum teleportation. So if A wants to send an encrypted message to B, they use entanged particles to choose an encryption key. Nobody else can snoop on the key, since it is not "sent" from one to the other. Two identical keys just "appear" at A and B, A uses it to encrypt his message before sending it (classically, for example using a homing pigeon) to B who then uses the same key to decrypt it.
  Being able to create a shared key instantaneously (if the setup has already been done before) and without anyone being able to snoop on it, is very useful indeed. And in theory, you can make the key as long as the message so there's absolutely no chance at all of anyone breaking the "code".
28. Re:If I recall..... by SuricouRaven · 2012-09-06 04:18 · Score: 2
  
  Encryption. Mathematically-proven-to-be-unbreakable encryption.
29. Re:If I recall..... by Nemyst · 2012-09-06 05:23 · Score: 2
  
  Quantum correlations do exist and are part of the description of quantum mechanics. They do not however allow to transmit information, since the correlations are purely random.
30. Re:If I recall..... by SolitaryMan · 2012-09-06 05:32 · Score: 2
  
  Honest question: what exactly is the point then?
  
  --
  May Peace Prevail On Earth
31. Re:If I recall..... by LordLimecat · 2012-09-06 05:36 · Score: 3, Funny
  
  and a Nobel Prize for whoever figured it out.
  I thought you had to do something political to get one of those.
32. Re:If I recall..... by tnk1 · 2012-09-06 05:42 · Score: 3, Informative
  
  Yes and no.
  Probability is very important, but it is not the measurement, or at least not the initial measurements, which are the issue.
  The measurements on the particles will actually be the spookily transmitted values that you would expect. If person A observes his particle and locks in a state, the particle of person B will instantly take on the mirror or opposite of what person A has measured. Until entanglement is broken, particle B will remain in that state for person B to discover almost at their leisure. So, you *can* measure two particles and get the same/mirror answer... but only once per particle.
  Or in other words, if Person A observes a living Schrodinger's Cat in his box, Person B will get a dead one in his entangled box instantly, which will be there for him to see when he opens the box. It will not go back to being uncertain until the box is opened and then closed again. Person B does get the opportunity to see the state of his particle as changed by entanglement.
  So what is the problem? Sounds like this is faster than light. And it is. However, Relativity does not state that nothing can happen faster than light, only that *information* cannot be transmitted faster than light. The problem is entanglement does not actually create a channel for passing information by itself.
  For information to be passed one side must use a channel to send a message to the other. With entanglement you will have "sent" a state, but the other side has no way of knowing you actually sent a message, which in turn means that information is not passed.
  Remember, collapsing the probabilities and killing/not killing a cat can be done by *either side*. That means that if you open your box and find a living cat, it could mean that your partner earlier opened his box and found his cat was dead (and is attempting to send you a message). Alternately, it might mean he hadn't gotten around to opening his box yet and you opened first, making you are responsible for killing his cat which he may soon discover (you monster).
  This is *not* insurmountable normally. If you could, say, ensure that you always kill the cat in your box when you are sending a message, then I could use frequency analysis or some other algorithm on all of my living cat results because I know that only living cats can be message data. There would still be a ratio of noise to the signal due to the ever present possibility that I am killing his cat on the other side by looking before he does, but you should be able to wring data out of it. You would, of course, need multiple entangled boxes for this, but other than representing mass cat murder, this is not a major problem.
  Unfortunately, this is where the Uncertainty Principle checkmates us. When you open a box, it is always completely random what you get. You can't force a result or know ahead of time what you will send, so pre-arranging to only accept one result is pointless. Even the smallest attempt to alter the box before opening it in a manner that would make the result even slightly more predictable counts as a measurement and trips the entanglement effect. Then when you go to look in the box afterward, you are simply looking at particle that is no longer entangled. In effect, altering the box in any useful way is the same thing as opening it.
  So, to actually send a decipherable message, you need a classical, slower than light channel to decipher every bit of information you send via entangled particles. While it is technically true that your actual bits arrived faster than light, the information is 100% indecipherable until you get the decoder for each bit at light speed, and so there is no way to disseminate actual information faster than light in this way.
33. Re:If I recall..... by Anonymous Coward · 2012-09-06 05:53 · Score: 2, Interesting
  
  What you are describing is quantum entanglement, not quantum teleportation. Quantum teleportation needs quantum entanglement to work, but they are two very different things.
  With quantum teleportation, the sender absolutely does get to choose the message. The message can be any quantum state. You still can not send messages faster than light of course. To send one qubit, the sender needs to send two classical bits (and use one pair of pre-entangled qubits). You are limited by how fast you can send the two classical bits. If you have a classical message to send, you might as well just send it normally.
34. Re:If I recall..... by Urza9814 · 2012-09-06 06:18 · Score: 2
  
  No, you wouldn't. The wheel is made up of individual particles. It bends, it compresses, it shrinks...it seems to be solid and move instantly, but that is only because it is too small to see these effects.
  Say you have a giant steel rod from the Earth to Pluto. You push on this rod. You would think that the rod would move forward on Pluto at the instant you push on it, allowing FTL binary communication. But it doesn't. You push on the rod and it creates a pressure wave travelling through the rod around the speed of sound. The molecules of steel can compress and move, and they have a top speed. In the end, it's actually going to be a while before that push is felt at the other end.
35. Re:If I recall..... by Chris+Burke · 2012-09-06 06:55 · Score: 2
  
  The Higgs boson was also a common myth
  That doesn't even make sense... The Higgs Boson was a prediction of the same model of the universe which says that quantum entanglement can't be used for FTL communication. The experimental verification of that prediction is further evidence for the model.
  The myth is that quantum entanglement as we understand it would allow for FTL communication, when reality is that this phenomenon as understood does not.
  It's possible that we're wrong, but your example is the opposite of supporting the idea that we might be.
  
  --
  
  The enemies of Democracy are
36. Re:If I recall..... by Grishnakh · 2012-09-06 07:36 · Score: 2
  
  They're two different prizes with the same name and somewhat under the same group. The "real" Nobel prizes are in the sciences, and are actually awarded for real accomplishments. It's just the stupid Peace Prize that's been turned into a laughingstock. It's probably not the same people who decide to award those prizes. The ones who gave the PP to Obama should be outcast for their idiocy, and never allowed to decide any more prizes for anything again.
37. Re:If I recall..... by Grishnakh · 2012-09-06 07:49 · Score: 2
  
  I'm pretty sure the Alcubierre Drive does not violate causality or presume time travel.
38. Re:If I recall..... by MozeeToby · 2012-09-06 08:58 · Score: 2
  
  You don't understand. We don't know everything about the universe or about physics but we do know some things beyond any reasonable doubt. Relativity is one of those things, specifically time dialation; GPS relies on it, we can put an atomic clock in an airplane and predict how much it will vary from a stationary one at ground level based on altitude and speed. It has been empirically verified.
  You cannot have a universe with all three A) Time dilation in line with relativity B) FTL is possible and C) Causality. The three taken together are incompatible. FTL + Time dilation allows for sending messages into the past, breaking causality. Since we know A is true, either B or C must be false (or both I suppose). Therefore I have to choose, a universe that allows FTL or a universe that has causality. IMO assuming causality is true is the lesser assumption and via Occam's Razor I'm left with no FTL.
39. Re:If I recall..... by hairyfeet · 2012-09-06 10:49 · Score: 2
  
  The problem is until we truly understand the quantum levels frankly we don't know shit. All we can really say is "With the data we have now FTL is impossible" but that data could change tomorrow, hell we aren't even sure how many dimensions there are or what the hell is going on when we get to the micro and macro at cosmic scales.
  Don't forget Einstein spent the last 20 years of his life trying to disprove quantum because in his words "God doesn't play dice" and now we know that even Einstein could blow it occasionally. Do I think FTL is possible? who knows? Again all I can say with certainty is "With the data we have FTL is impossible" but the wise man knows that his knowledge is woefully limited. Hell if you'd have brought someone from just 2 centuries ago, a blink of an eye in cosmic scale, to today he'd have thought the whole thing was magic. In another 2 centuries who the hell knows what rules we'll have to rewrite, what discovers we'll make, personally I think its exciting as hell.
  
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40. Re:If I recall..... by lennier · 2012-09-06 11:28 · Score: 2
  
  Do you have any reason to suspect that our understanding of quantum mechanics is generally unreliable or flawed in a relevant way?
  Sure we do. One, the existence of extra infinities in QED which renormalisation works around shows that quantum field theories can't be the last mathematical word; they're at best an approximation which works as long as we don't extend it to all cases.
  Two, the Standard Model containing a huge number of plugged-in variables shows that we don't yet have a fundamental theory which generates those numbers.
  Three, the fact that we've yet to achieve a workable theory of quantum gravity despite >50 years of extremely bright effort shows that there are major fundamental mathematical incompatibilities between QED/QCD and General Relativity. The continuing failure of string theory to find its way out of the landscape problem suggests that such a mathematical resolution might not even exist.
  Four, the laser, one of the most spectacular achievements of post-WW2 physics, actually was considered impossible by some of the leading QM theorists of the time. It works, but why did the theory suggest it wouldn't? Food for thought.
  Five (although this generally worries philosophers and laypeople a lot more than it worries trained physicists, for some reason), at a deeper philosophical level the number of arbitrary postulates and principles which get waived and fudged on an ad-hoc fashion in the entire field of QM really ought to give us much pause. Relativity assumes a smooth continuum but QM assumes integer values of very small quantities, except where it doesn't (1/2 spin and 1/3 charge; why are fractions allowed in a supposedly final theory?) Parity is always conserved, except where it isn't. Spacetime ought to be quantized, but maybe it isn't. The wavefunction itself probably isn't quantized, but why? Spin isn't really spin, it's just a number. Fundamental particles are modelled as infinitely small points, but that would assume infinite energy density, which not only isn't quantizable, it doesn't really make sense. Antimatter is indistinguishable from ordinary matter travelling backwards in time (Feynman), but there's apparently no predictions that this makes, despite it being a huge reversal to our ordinary notions of causality. The proton is made of three quarks, except that it isn't; it's actually a uncountable sea of virtual quarks. What are virtual particles made of - it's obviously not "nothing" if it interacts - and why do we need to assume all this?
  There's no wider motivation to any of these assumptions and many of them are mutually contradicting; except that each was introduced to solve a specific problem and then generated its own. To the outside observer, all this looks disturbingly like a series of Ptolemaic epicycles. Classical physics from Newton to Maxwell was clean and simple, required very few postulates to explain a wide range of phenomena, and was easy to explain. The fundamentals were small and logical and worked together without edge cases. Post-Einstein physics seems increasingly to be moving in the opposite direction: a huge bloated kernel where the "fundamental" layer is actually more complicated than the simpler emergent phenomena it claims to explain. This intuitively feels like it's putting the cart before the horse? But since Einstein and Bohr, "intuition" has been increasingly discredited in physics, and "counterintutitive" is seen as high praise, so there's not much leverage for philosophical criticism. And the sheer brute success of, eg, atomic explosions has been seen as empirical justification of the whole subatomic physics enterprise. But - to an outsider - it feels that, despite there being a huge volume of paper produced, basic physics progress (as opposed to engineering) is actually slowing exponentially since WW2, not accelerating.
  
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41. Re:If I recall..... by 0x537461746943 · 2012-09-06 21:10 · Score: 2
  
  I read an article that researches slowed light down to an almost stand still awhile back. So what would happen if you slowed light down on one of the two entangled particles and then read the one that was not slowed down? Would the slowed down light particle then flip to what it should be or would is take awhile for it to do so? It would be an interesting test I think.
Put Another Way by Anonymous Coward · 2012-09-06 01:35 · Score: 5, Insightful

So, it's not teleportation. Thanks.
Why Satellites? by sergioag · 2012-09-06 01:35 · Score: 4, Insightful

If you are using quantum teleportation, why you even need a satellite???
1. Re:Why Satellites? by operagost · 2012-09-06 01:41 · Score: 2
  
  And what does God need with a star ship?
  
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2. Re:Why Satellites? by wonkey_monkey · 2012-09-06 01:58 · Score: 2
  
  Because it's not the kind teleportation you're thinking of. You still need a classical channel.
  
  --
  systemd is Roko's Basilisk.
3. Re:Why Satellites? by s_p_oneil · 2012-09-06 02:32 · Score: 2
  
  I think his point was valid. If instant communication is possible between a hub in the US and a hub in without wires or line-of-sight issues, there's little point spending the money to put those communication hubs into orbit. Sure we'd still have classical channels leading from those hubs, and we'd still need satellites for things like GPS, but the need for communication satellites would be greatly reduced.
  Of course, the point is moot if the bandwidth sucks on these things. If it's 300 baud, I don't care how amazing the ping time is. ;-)
Re:Why the Canaries of all places? by Anonymous Coward · 2012-09-06 01:38 · Score: 5, Funny

It's to provide early warning in the event of a quantum accident - you know something went wrong when the Canaries are both alive and dead.
I don't understand by Anonymous Coward · 2012-09-06 01:39 · Score: 2, Insightful

I don't understand exactly what's going on, so that probably explains why I don't see the advantage of this.
From reading the abstract I get the impression that they are transmitting the information via lasers to the other location.
How is this different then using other frequencies in the spectrum? Aren't you still limited to the speed of light? So what is the advantage of this?
Seems like it adds complication without gaining much, other than being quantum.
1. Re:I don't understand by locofungus · 2012-09-06 01:53 · Score: 2
  
  I agree and I was hoping someone else would have commented by now.
  TFS talks about efficiency. I can only guess that they can improve the bandwidth of the communication by using quantum teleportation but I'm not sure how and would be intrigued to find out.
  Tim.
  
  --
  God said, "div D = rho, div B = 0, curl E = -@B/@t, curl H = J + @D/@t," and there was light.
2. Re:I don't understand by dingen · 2012-09-06 01:58 · Score: 2
  
  The main advantage is that it uses a lot less power.
  
  --
  Pretty good is actually pretty bad.
Re:ping times by Dunbal · 2012-09-06 01:42 · Score: 3, Funny

Your 1ms ping time will be in compensation for your 80% packet loss.

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Seven puppies were harmed during the making of this post.
Comment removed by account_deleted · 2012-09-06 01:44 · Score: 3, Insightful

Comment removed based on user account deletion
HOLY SHIT IT'S THE REPLICATOR! by Anonymous Coward · 2012-09-06 01:46 · Score: 3, Funny

"Quantum teleportation is not how it is made out in Star Trek though. Instead of sending an object (in this case a photon) from one location to another; the information of its quantum state is sent, making a photon on the other end look identical to the original."
So since matter is energy, if you can make the quantum state of object A identical to object B, IT'S THE REPLICATOR FROM STAR TREK ZOMFG I WANNA CHEESEBURGER
Re:Why the Canaries of all places? by Anonymous Coward · 2012-09-06 01:53 · Score: 2, Informative

Because they had a telescope on the islands that could be directed at transmitter 143 km away over open ocean. It just happened these islands already had the things this experiment needed.
Re:How does this qualify as "teleportation"? by ledow · 2012-09-06 01:55 · Score: 4, Informative

It's not quite as simple as teleportation, it's just given that name:
https://en.wikipedia.org/wiki/Quantum_teleportation
Most specifically:
"Suppose Alice has a qubit in some arbitrary quantum state
The components of a maximally entangled two-qubit state are distributed to Alice and Bob.
In the end, the qubit in Bob's possession will be in the desired state."
So what Alice is doing is actually modifying the REMOTE qubits to be identical to the LOCAL qubits AFTER the initial information exchange has occurred. You're now literally turning someone's remote blank paper into a copy of the document you have yourself by using a little set of numbers that you determined between yourself last week.
Well - that explains Fermi's Paradox. by SoupIsGood+Food · 2012-09-06 02:08 · Score: 2

The reason why we aren't receiving radio signals from distant civilizations is that they're not using radios to communicate... they've figured out something better.
Re:Why the Canaries of all places? by captainpanic · 2012-09-06 02:10 · Score: 3, Insightful

I think we should mod this 'hilarious' instead of funny. 10 points, sir A. Coward.
Re:Why the Canaries of all places? by jellomizer · 2012-09-06 02:15 · Score: 2

If you are going to scientific research.
You have a choice.
Montana,
Siberia,
or
Some tropical island. Where would you choose?

--
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Re:Why the Canaries of all places? by PolygamousRanchKid+ · 2012-09-06 02:21 · Score: 2

The Canary Islands are the Cancun and Las Vegas of Europe: a boozy sun sex sand party romp. Where else would you travel with research grant money?
Although, what happens is Vegas, stays in Vegas, so I am not sure if Quantum Information can be transmitted outside the islands.

--
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
Re:Uses by pedestrian+crossing · 2012-09-06 02:24 · Score: 2

I wonder how much data can be transmitted with this technology.
None.

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A house divided against itself cannot stand.
Re:How does this qualify as "teleportation"? by Princeofcups · 2012-09-06 02:53 · Score: 2

You have two cats, one live an one dead. You put them in identical boxes, shuffle them around, and send one random box to someone across the country. When they get the box, they call you up and ask, "what did you send me?" You open your box, and if it's a live cat, you say "I sent you a dead cat," or visa versa.
No cats were harmed in this description.

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The only thing worse than a Democrat is a Republican.
Re:How does this qualify as "teleportation"? by Theaetetus · 2012-09-06 03:09 · Score: 2

For example, does it mean that it is like if I have a set of 2 blank pages. I give you one. You go home, I go home. Then later in that day, I write something on my blank page. At this exact moment, the same modifications are applied on your blank page ?
No, more like you have a set of 2 blank pages, and you write "A" and "B" on them. You then seal them in envelopes, shuffle them randomly, and give me one. We go to our separate homes. Later in the day, you open your envelope and see it says "B". You call me up and tell me on the phone that my paper says "A", even though I've not opened my envelope, and magically, you're right!
Re:Not Star Trek transporters, but communicators! by dingen · 2012-09-06 03:13 · Score: 2

I should know better than to discuss Star Trek on Slashdot.

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Pretty good is actually pretty bad.
someone please explain this to me by PJ6 · 2012-09-06 03:46 · Score: 3, Interesting

It is the hope of the research team that this experiment will lead to commercial use of quantum teleportation to interact with satellites and ground stations. This will increase the efficiency of satellite communication...
You can't send information via quantum teleportation, so exactly how do they plan to use it in satellite communication?
"same time" = what? by Datoyminaytah · 2012-09-06 05:35 · Score: 2

OK, here are my questions:

Assume two entangled particles, two synchronized atomic clocks, and two observers. Each observer has agreed to measure the state of their particle at a predetermined time, relative to their atomic clock. Assume one observer/clock/particle is on a spaceship that has been traveling near the speed of light for some time.

What happens when the particles are observed? Will the results be the same, because somehow time is "linked" even though it seems to pass differently for each observer? Will the results be different, because the particles are somehow linked "instantaneously?" (What does that even mean in this context?)

If the former, what happens if the particle is brought back to Earth? We should find the atomic clocks were no longer synchronized. (This part has been tested, right?) If so, wouldn't that mean the particles were permanently out of sync, and that by observing one of them, one could predict the future state of the other? As in, predicting the future?

IANAP, just pointing out some apparent paradoxes that for all I know have been solved.

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assert(birth_date<time-86400)
The PRACTICAL application by EnergyScholar · 2012-09-06 05:48 · Score: 2

The practical application is that any teleportation/entanglement based Quantum Neural Networks (QNN) that happen to already exist on and around planet Earth communicate between nodes via quantum teleportation. Thus, the maximum Quantum Teleportation (QT) range is also the maximum distance between nodes. I happen to know that earth-orbital QT distances have been practical for one QNN for more than ten years, so it's about time that 'official' science caught up with this. Readers should note that the existence of ANY practical QNN remains classified, hidden, and secretive, although information about this advanced new (well, 22 years old, but newish) technology is gradually leaking out.
Note that, as several people have pointed out, there must be a [steganographic] classical back channel to actually accomplish communication between nodes.
So what happens if. . . by JSBiff · 2012-09-06 06:06 · Score: 2

So what happens if two particles or photos are entangled, and are seperated by enough distance that there is human-scale lag (say 1/2 second to one second), and both ends of the link attempt to transmit at about the same time?
Would that break the entanglement? Or would the information "pass each other" on the way, and each particle takes on the state that the other particle used to have - now they are still both entangled, but aren't in sync? Would a change to one without changing the other re-establish the synchronization? Would the changes oscillate back and forth in a sort of "standing wave"?
Bop Ad (Douglas Adams) by Stolzy · 2012-09-06 18:37 · Score: 2

I think Douglas Adams got it right on that front. In Hitchhiker's Guide To The Galaxy he wrote about technology increasing at such a rate that the old "warships" which had been sent off to fight intergalactic wars arrived to find the wars had already been fought and won. Meaning, in 100 years from now our space travel technology will be so far advanced of the Voyager satellites that we could, essentially, travel out to them, pick them up, and return to Earth in 1/100th the time it took for them to travel the total distance they will have potentially travelled up to that time. Hypothetically speaking.