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One thing that isn't clear in this article is whether they really teleportated it, meaning that they were able to transfer information instantaneously from poin

One thing that isn't clear in this article is whether they really teleportated it, meaning that they were able to transfer information instantaneously from point A to point B (which would go against Einstein's relativity law that states that nothing can go faster than the speed of light), or if they just transported a light beam from one point to another with regular means of communication. It sounds more like it's the later case, and the word "teleportation" here is probably more a link bait than anything else. And in any case, the title in the article is horrible: "Scientists teleport Schrodinger's cat"

burgerbrain 16y ago
Quantum teleportation does not allow for faster than light transmission of information. "It does not transport the system itself, nor does it allow communication of information at superluminal (faster than light) speed." https://secure.wikimedia.org/wikipedia/en/wiki/Quantum_teleportation https://secure.wikimedia.org/wikipedia/en/wiki/Quantum_telep... I doubt this is different.
- cpeterso 16y ago
  Subspace radio allows for faster than light communication.
  - pavel_lishin 16y ago
    Magic, too.
Saavedro 16y ago
This is not FTL no, that's still impossible and if they'd done -that- this would be a big deal indeed. What this allows is simply transmitting "quantum information" from one place to another with any reliability at all, by packing it with classical information that helps accomplish that (being the macro-object/light packet). http://en.wikipedia.org/wiki/No-teleportation_theorem http://en.wikipedia.org/wiki/No-teleportation_theorem explains why transmission of quantum information is difficult. http://en.wikipedia.org/wiki/No-communication_theorem http://en.wikipedia.org/wiki/No-communication_theorem explains why quantum effects do not enable FTL transfer of classical information.
baddox 16y ago
The speed limit of the universe isn't just some hypothesis waiting to be disproven. It can't be broken. It's impossible.
- mmavnn 16y ago
  Never underestimate the capacity of humans to be wrong. Science is made from people being willing to admit they're wrong: the evidence for speed limits is compelling, but not absolute. It would just mean our current model is screwed if we're wrong...
  - baddox 16y ago
    Assuming that the speed of light can be broken leads to hopelessly contradictory and paradoxical (truly paradoxical, not just counterintuitive) conclusions. It's not just some guess that scientists have made about how fast information can travel.
- arethuza 16y ago
  Scientific theories aren't reality - they are a model of reality and to be considered scientific a theory has to be refutable - if you can't conceive of experimental results that would disprove your theory then it's not really a scientific theory. So every scientific theory is in a very real sense "waiting to be disproven".
  - baddox 16y ago
    We can know things. We know that no algorithm can determine whether or not arbitrary Turing machines will halt, because assuming the contrary leads to a contradiction. Similarly, no consistent axiomatic system powerful enough to express propositions of elementary arithmetic can be complete. Neither the undecidability of the halting problem nor Gödel's first incompleteness theorem are "waiting to be disproven." Similarly, the speed limit of the universe, if assumed to be breakable, leads to all sorts of contradictions and true paradoxes. Note that I'm not saying that the entirety of some theory, be it special or general relativity, quantum theory, etc. are known truths.
geuis 16y ago
It's explicitly clear in the article that this isn't "instantaneous" travel. As much as I hate the analogy, they basically were able to copy the box, the cat, the Geiger counter, and the radioactive trigger wholesale and transmit the copy somewhere else. Normally the process of copying would mean someone had to look in the box. This time they were able to copy the package without finding out if Heathcliff was alive or dead.
invalidOrTaken 16y ago
and the word "teleportation" here is probably more a link bait than anything else. One thing I like about HN is that if I see a link that sounds too, umm, bait-y, I can just look at the comments here and avoid wasting my time (or at least getting excited without cause).
jnhnum1 16y ago
Quantum teleportation just means reproducing the entire quantum state of the system without physically transporting it. It's interesting to note that you can't do this without destroying the original (http://en.wikipedia.org/wiki/No-cloning_theorem http://en.wikipedia.org/wiki/No-cloning_theorem).
ElliotH 16y ago
It would appear that they did. The abstract of Lee et Al's report states: "We report on the experimental quantum teleportation of strongly nonclassical wave packets of light. To perform this full quantum operation while preserving and retrieving the fragile nonclassicality of the input state, we have developed a broadband, zero-dispersion teleportation apparatus that works in conjunction with time-resolved state preparation equipment. Our approach brings within experimental reach a whole new set of hybrid protocols involving discrete- and continuous-variable techniques in quantum information processing for optical sciences." [1] The abstract as a whole is a little beyond my knowledge of physics, but the way I read it seems to support that they did actually teleport - but in the quantum sense (ie they destroyed and recreated something in the same quantum state, not that they moved in instantaneously). Another Science article in the same issue supports my reasoning "Such exotic quantum states can now be prepared in the lab, and even better, they can be teleported—that is, destroyed in one place and recreated in another one, as shown by Lee et al. (1) on page 330 of this issue." [2] [1] - "Teleportation of Nonclassical Wave Packets of Light" - http://www.sciencemag.org/content/332/6027/330 http://www.sciencemag.org/content/332/6027/330 (Science 15 April 2011: Vol. 332 no. 6027 pp. 313-314) [2] - "Make It Quantum and Continuous" - http://www.sciencemag.org/content/332/6027/313.full http://www.sciencemag.org/content/332/6027/313.full (Science 15 April 2011: Vol. 332 no. 6027 pp. 313-314)
jessriedel 16y ago
"Teleportation" is a precise term in the field of quantum information; it wasn't the choice of the news article. Yes, the term was chosen to sound sexy, but it's not an unreasonable term for what it describes even if it can't quite live up to Star Trek.

burgerbrain 16y ago

Quantum teleportation does not allow for faster than light transmission of information. "It does not transport the system itself, nor does it allow communication of information at superluminal (faster than light) speed." https://secure.wikimedia.org/wikipedia/en/wiki/Quantum_teleportation https://secure.wikimedia.org/wikipedia/en/wiki/Quantum_telep... I doubt this is different.

cpeterso 16y ago
Subspace radio allows for faster than light communication.
- pavel_lishin 16y ago
  Magic, too.

Saavedro 16y ago

This is not FTL no, that's still impossible and if they'd done -that- this would be a big deal indeed. What this allows is simply transmitting "quantum information" from one place to another with any reliability at all, by packing it with classical information that helps accomplish that (being the macro-object/light packet). http://en.wikipedia.org/wiki/No-teleportation_theorem http://en.wikipedia.org/wiki/No-teleportation_theorem explains why transmission of quantum information is difficult. http://en.wikipedia.org/wiki/No-communication_theorem http://en.wikipedia.org/wiki/No-communication_theorem explains why quantum effects do not enable FTL transfer of classical information.

baddox 16y ago

The speed limit of the universe isn't just some hypothesis waiting to be disproven. It can't be broken. It's impossible.

mmavnn 16y ago
Never underestimate the capacity of humans to be wrong. Science is made from people being willing to admit they're wrong: the evidence for speed limits is compelling, but not absolute. It would just mean our current model is screwed if we're wrong...
- baddox 16y ago
  Assuming that the speed of light can be broken leads to hopelessly contradictory and paradoxical (truly paradoxical, not just counterintuitive) conclusions. It's not just some guess that scientists have made about how fast information can travel.
arethuza 16y ago
Scientific theories aren't reality - they are a model of reality and to be considered scientific a theory has to be refutable - if you can't conceive of experimental results that would disprove your theory then it's not really a scientific theory. So every scientific theory is in a very real sense "waiting to be disproven".
- baddox 16y ago
  We can know things. We know that no algorithm can determine whether or not arbitrary Turing machines will halt, because assuming the contrary leads to a contradiction. Similarly, no consistent axiomatic system powerful enough to express propositions of elementary arithmetic can be complete. Neither the undecidability of the halting problem nor Gödel's first incompleteness theorem are "waiting to be disproven." Similarly, the speed limit of the universe, if assumed to be breakable, leads to all sorts of contradictions and true paradoxes. Note that I'm not saying that the entirety of some theory, be it special or general relativity, quantum theory, etc. are known truths.

geuis 16y ago

It's explicitly clear in the article that this isn't "instantaneous" travel. As much as I hate the analogy, they basically were able to copy the box, the cat, the Geiger counter, and the radioactive trigger wholesale and transmit the copy somewhere else. Normally the process of copying would mean someone had to look in the box. This time they were able to copy the package without finding out if Heathcliff was alive or dead.

invalidOrTaken 16y ago

and the word "teleportation" here is probably more a link bait than anything else. One thing I like about HN is that if I see a link that sounds too, umm, bait-y, I can just look at the comments here and avoid wasting my time (or at least getting excited without cause).

jnhnum1 16y ago

Quantum teleportation just means reproducing the entire quantum state of the system without physically transporting it. It's interesting to note that you can't do this without destroying the original (http://en.wikipedia.org/wiki/No-cloning_theorem http://en.wikipedia.org/wiki/No-cloning_theorem).

ElliotH 16y ago

It would appear that they did. The abstract of Lee et Al's report states: "We report on the experimental quantum teleportation of strongly nonclassical wave packets of light. To perform this full quantum operation while preserving and retrieving the fragile nonclassicality of the input state, we have developed a broadband, zero-dispersion teleportation apparatus that works in conjunction with time-resolved state preparation equipment. Our approach brings within experimental reach a whole new set of hybrid protocols involving discrete- and continuous-variable techniques in quantum information processing for optical sciences." [1] The abstract as a whole is a little beyond my knowledge of physics, but the way I read it seems to support that they did actually teleport - but in the quantum sense (ie they destroyed and recreated something in the same quantum state, not that they moved in instantaneously). Another Science article in the same issue supports my reasoning "Such exotic quantum states can now be prepared in the lab, and even better, they can be teleported—that is, destroyed in one place and recreated in another one, as shown by Lee et al. (1) on page 330 of this issue." [2] [1] - "Teleportation of Nonclassical Wave Packets of Light" - http://www.sciencemag.org/content/332/6027/330 http://www.sciencemag.org/content/332/6027/330 (Science 15 April 2011: Vol. 332 no. 6027 pp. 313-314) [2] - "Make It Quantum and Continuous" - http://www.sciencemag.org/content/332/6027/313.full http://www.sciencemag.org/content/332/6027/313.full (Science 15 April 2011: Vol. 332 no. 6027 pp. 313-314)

jessriedel 16y ago

"Teleportation" is a precise term in the field of quantum information; it wasn't the choice of the news article. Yes, the term was chosen to sound sexy, but it's not an unreasonable term for what it describes even if it can't quite live up to Star Trek.