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Science Forum

  1. Standard member Ghost of a Duke
    The voice of reason
    13 Jul '17 07:24
    Need a little help to get my head around this. The Time's reports that scientists have managed to teleport an object Into space!

    'A team of researchers in China sent a photon from the ground to an orbiting satellite more than 300 miles above through a process known as quantum entanglement, according to MIT Technology Review. It’s the farthest distance tested so far in teleportation experiments, the researchers said. Their work was published online on the open access site arXiv.

    'For about a month, the scientists beamed up millions of photons from their ground station in Tibet to the low-orbiting satellite. They were successful in more than 900 cases.'
  2. 13 Jul '17 07:39
    Looks to me like the 'teleport' word is being misused. It could be a translation issue, or it could be a reporting issue, or it could be the scientists being a bit over enthusiastic.
  3. 13 Jul '17 07:49 / 1 edit
    Originally posted by Ghost of a Duke
    Need a little help to get my head around this. The Time's reports that scientists have managed to teleport an object Into space!

    'A team of researchers in China sent a photon from the ground to an orbiting satellite more than 300 miles above through a process known as quantum entanglement, according to MIT Technology Review. It’s the farthest dis ...[text shortened]... nd station in Tibet to the low-orbiting satellite. They were successful in more than 900 cases.'
    I heard this on the radio; it's facinating but I suspect the scientists are struggling to gain sufficient impetus to overcome the "so what now?" headwind they are coming into. Language such as "beamed up" may be appealing to the masses but is hardly likely to gain them any scientific or fiscal traction. Besides, as I understand it, whatever is beamed is destroyed at a molecular/particle level and reconstructed. Hence why they can only use a photon. Also, is it right to call a photon an "object". Good fun reading/listening though.
  4. Standard member sonhouse
    Fast and Curious
    13 Jul '17 11:26
    Originally posted by Ghost of a Duke
    Need a little help to get my head around this. The Time's reports that scientists have managed to teleport an object Into space!

    'A team of researchers in China sent a photon from the ground to an orbiting satellite more than 300 miles above through a process known as quantum entanglement, according to MIT Technology Review. It’s the farthest dis ...[text shortened]... nd station in Tibet to the low-orbiting satellite. They were successful in more than 900 cases.'
    What it means is a photon ended up at the space station with exactly the same energy, spin and so forth as one that was on the ground. Teleport is a very poor word for this since it cannot happen at more than the speed of light. It really means a photon was analysed on Earth and they managed to have one in orbit that matched all the energy and polarization and such of the one on the ground.

    The same photon generated was definitely NOT teleported into orbit.
  5. Standard member Ghost of a Duke
    The voice of reason
    13 Jul '17 11:45
    Originally posted by sonhouse
    What it means is a photon ended up at the space station with exactly the same energy, spin and so forth as one that was on the ground. Teleport is a very poor word for this since it cannot happen at more than the speed of light. It really means a photon was analysed on Earth and they managed to have one in orbit that matched all the energy and polarization ...[text shortened]... of the one on the ground.

    The same photon generated was definitely NOT teleported into orbit.
    Ah, that's a shame. (But what I expected). As Dive said though, made interesting reading.

    Beam me up Scotty.
  6. 13 Jul '17 13:09
    Originally posted by Ghost of a Duke
    Need a little help to get my head around this. The Time's reports that scientists have managed to teleport an object Into space!

    'A team of researchers in China sent a photon from the ground to an orbiting satellite more than 300 miles above through a process known as quantum entanglement, according to MIT Technology Review. It’s the farthest dis ...[text shortened]... nd station in Tibet to the low-orbiting satellite. They were successful in more than 900 cases.'
    First of all, this is not the first demonstration of quantum entanglement over long distances - just the first demonstration (if confirmed) through space.

    Secondly, what is "teleported" is not the object itself but rather some information (e.g. polarization of a photon) associated to the object.
  7. Subscriber FreakyKBH
    Acquired Taste...
    13 Jul '17 14:22
    Originally posted by KazetNagorra
    First of all, this is not the first demonstration of quantum entanglement over long distances - just the first demonstration (if confirmed) through space.

    Secondly, what is "teleported" is not the object itself but rather some information (e.g. polarization of a photon) associated to the object.
    Anything over "long distances" is also "through space."
  8. 13 Jul '17 14:29
    Originally posted by FreakyKBH
    Anything over "long distances" is also "through space."
    Thanks for that insightful contribution, Freaky. Previous experiments were conducted where the "teleportation" was between two laboratories located on Earth. I thought of explaining that in my post but reconsidered since I assumed the number of morons reading the post would be fairly limited.
  9. Subscriber FreakyKBH
    Acquired Taste...
    13 Jul '17 14:57
    Originally posted by KazetNagorra
    Thanks for that insightful contribution, Freaky. Previous experiments were conducted where the "teleportation" was between two laboratories located on Earth. I thought of explaining that in my post but reconsidered since I assumed the number of morons reading the post would be fairly limited.
    You forgot: some morons prefer precision.
  10. 13 Jul '17 15:47
    Originally posted by KazetNagorra
    First of all, this is not the first demonstration of quantum entanglement over long distances - just the first demonstration (if confirmed) through space.

    Secondly, what is "teleported" is not the object itself but rather some information (e.g. polarization of a photon) associated to the object.
    It wasn't clear whether they were actually carrying out teleportation. Entangled photons is NOT teleportation. Using entangled photons to move a quantum state IS, but that requires further setup. I didn't actually see that extra setup mentioned in the article.
  11. 13 Jul '17 15:50
    Originally posted by sonhouse
    Teleport is a very poor word for this since it cannot happen at more than the speed of light.
    Teleportation in the Star Trek setting may happen at the speed of light. It is always used over short distances. It involves destroying an object and recreating it exactly at a new location. With quantum teleportation, that is what is done. It is never instantaneous and involves sending information separately from the entangled photon. The entangled photons DO NOT transmit information, they merely ensure identical quantum states.
  12. Standard member sonhouse
    Fast and Curious
    13 Jul '17 15:52
    Originally posted by twhitehead
    It wasn't clear whether they were actually carrying out teleportation. Entangled photons is NOT teleportation. Using entangled photons to move a quantum state IS, but that requires further setup. I didn't actually see that extra setup mentioned in the article.
    But the movement of the quantum state still takes place at exactly c velocity, right?
  13. 13 Jul '17 16:06
    I have a pair of shoes, one left and one right shoe.

    I took one of the shoes, at random, I didn't know exactly which one, and sent this shoe to Antarctica where I have a friend. He took it up from the package and exactly the same time when he discovered which one he'd got, the right one or the left one, the information of what shoe was at my side.

    Question: The information about the left/right-ness of my shoe went to him (a) at the speed of light, or (b) instantaneously?

    Entanglement is not more mysterious than this.
  14. Standard member sonhouse
    Fast and Curious
    13 Jul '17 16:09
    Originally posted by FabianFnas
    I have a pair of shoes, one left and one right shoe.

    I took one of the shoes, at random, I didn't know exactly which one, and sent this shoe to Antarctica where I have a friend. He took it up from the package and exactly the same time when he discovered which one he'd got, the right one or the left one, the information of what shoe was at my side.

    Q ...[text shortened]... at the speed of light, or (b) instantaneously?

    Entanglement is not more mysterious than this.
    I'm pretty sure it takes place at c only.
  15. 13 Jul '17 16:33
    Originally posted by sonhouse
    But the movement of the quantum state still takes place at exactly c velocity, right?
    Its complicated. The actual flow of information takes place only at light speed or slower.

    Imagine you have a set of cards and on pairs of cards you write either 0 or 1 (same on each pair). Then you send off one of each pair to another person in another person in another country. You now can check 'card A' and know that the other person will find the exact same number as you do on 'card A'.
    So, instead of sending him a 0 or a 1, you send him 'look at card A'. He looks at card A. He then knows what you know, which is what was on card A.
    This, on its own, isn't really teleportation.
    But now you look at your cards, combine their values with your message, then send him the result. He can then use his cards to decode what you sent to get your message. So up to here, we are talking about a type of cryptography. Secure, but nothing special.
    Now suppose those cards were quantum, and had no defined value until you looked at them.
    When you look at yours, then instantaneously both take on a defined value (identical).
    Still not teleportation. But getting a little interesting.
    When combined with the above cryptography technique and used to recreate a particular quantum state - then we have teleportation.