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  1. Standard member apathist
    looking for loot
    24 Jul '16 18:22 / 1 edit
    Experiment #1
    So we build a teleportation machine here on Terra. Step into the booth and push the button, the machine performs a destructive scan and records all of the information about your physical body. Beam* the data to the receiving station at our colony on Mars. They precisely reconstruct your body according to the transmitted information, complete w/ jump-start if that sort of thing is necessary. So did you successfully teleport yourself to Mars?

    Experiment #2
    Now we can gather all that data about your physical body using a non-invasive scan! So while you sit there, bemused, we gather and send the data, and the receiving station on Mars builds a viable human being using that data. So did you successfully teleport yourself to Mars?

    Here is where apathist steps in with his dumb-ass consciousness-tracking methodology. I'm still on Terra, so clearly that ain't me on Mars. Experiment #2 is a fail. I'll point out that the collected data can be used to build multiple copies, and so I offer the apathist Axiom of Teleportation Technology (the aATT) which says if the teleportation technology can make multiple copies, no actual teleportation occurs. This means BOTH experiments are failures!

    * We could use drum beats instead of fancy modulated laser beams to send the data. We'd need a long air-filled tube and some amplifiers, but isn't it incredible to think that the entire sum of your actual physical existence can be reduced to a (long and boring) drum solo?
  2. 24 Jul '16 22:05
    Both experiments are successes and both are copying operations. But teleportation is a copying operation.
    This post will reach you via teleportation. It will not be the original, but a copy. And there will be many copies. But it will still be this post in every way, not a dot out of place. In fact, to believe that there is still an 'original' is an error.
    Similarly, in your teleportation experiments, if the system is perfect then there will be no 'original' once complete. Only multiple, indistinguishable copies, all with consciousness and all thinking they are the one true original.
  3. Standard member sonhouse
    Fast and Curious
    25 Jul '16 22:14
    qOriginally posted by twhitehead
    Both experiments are successes and both are copying operations. But teleportation is a copying operation.
    This post will reach you via teleportation. It will not be the original, but a copy. And there will be many copies. But it will still be this post in every way, not a dot out of place. In fact, to believe that there is still an 'original' is an erro ...[text shortened]... ndistinguishable copies, all with consciousness and all thinking they are the one true original.
    I have a question about superposition: If a quantum bit is in superposition say in 4 places at once, what is the total energy of the system? If you have 4 superpositioned photon's is that 1 photon in 4 places at once or 4 separate photons with the exact same properties as their twins? Or quad's? Was trying to see if there is some conservation of energy going on here that prevents one photon from becoming 4. It seems you would have to generate 4 separate photons but not sure.
  4. Standard member DeepThought
    Losing the Thread
    26 Jul '16 04:28 / 1 edit
    Originally posted by sonhouse
    I have a question about superposition: If a quantum bit is in superposition say in 4 places at once, what is the total energy of the system? If you have 4 superpositioned photon's is that 1 photon in 4 places at once or 4 separate photons with the exact same properties as their twins? Or quad's? Was trying to see if there is some conservation of energy goin ...[text shortened]... one photon from becoming 4. It seems you would have to generate 4 separate photons but not sure.
    Charge conjugation invariance prevents a single photon splitting into four photons. Essentially, the corresponding Feynman diagram would have five external legs and the number of external legs has to be even, otherwise anomalies would destroy gauge invariance. This does mean that one photon can split into three of lower frequency. There is a picture of the diagram on this Wikipedia page [1] in the context of photon-photon scattering, you can look at the triangle diagram on this page [2] whose amplitude is zero in QED but generates the chiral anomaly in QCD, and would correspond to one photon splitting into two.

    [1] https://en.wikipedia.org/wiki/Two-photon_physics
    [2] https://en.wikipedia.org/wiki/One-loop_Feynman_diagram
  5. Standard member sonhouse
    Fast and Curious
    26 Jul '16 06:04
    Originally posted by DeepThought
    Charge conjugation invariance prevents a single photon splitting into four photons. Essentially, the corresponding Feynman diagram would have five external legs and the number of external legs has to be even, otherwise anomalies would destroy gauge invariance. This does mean that one photon can split into three of lower frequency. There is a picture o ...[text shortened]... ikipedia.org/wiki/Two-photon_physics
    [2] https://en.wikipedia.org/wiki/One-loop_Feynman_diagram
    That makes sense, if it splits into 4 parts than if it starts as, say, a wavelength of 100 nanometers, it would end up with 4 photons of 400 nanometers, if I have that right, then energy is conserved.
  6. Standard member DeepThought
    Losing the Thread
    26 Jul '16 06:32
    Originally posted by sonhouse
    That makes sense, if it splits into 4 parts than if it starts as, say, a wavelength of 100 nanometers, it would end up with 4 photons of 400 nanometers, if I have that right, then energy is conserved.
    Energy conservation is not enough, gauge invariance has to be preserved as well, there are no anomalies in Quantum Electrodynamics so one photon cannot split into four. Also the amplitude for the box diagram [reference 1 above] is tiny. So a 1 TeV photon would split into three 333 GeV photons, but cannot split into four 250 GeV photons.
  7. Standard member apathist
    looking for loot
    29 Jul '16 22:36
    Originally posted by twhitehead
    Both experiments are successes and both are copying operations. But teleportation is a copying operation.
    This post will reach you via teleportation. It will not be the original, but a copy. And there will be many copies. But it will still be this post in every way, not a dot out of place. In fact, to believe that there is still an 'original' is an error ...[text shortened]... ndistinguishable copies, all with consciousness and all thinking they are the one true original.
    Originally posted by twhitehead
    Both experiments are successes and both are copying operations. But teleportation is a copying operation.
    Teleporting humans is not a copying operation. The op shows that copying is not sufficient for the teleportation of people.

    This post will reach you via teleportation.
    Electronic communication is not teleportation.

    Similarly, in your teleportation experiments, if the system is perfect then there will be no 'original' once complete. Only multiple, indistinguishable copies,...
    In the second experiment, the original is unchanged. The copies are built on Mars. The original is not one of the copies.

    Since the information sent in the first experiment would be the same information sent in the second experiment, we can see that only copies are built on mars, and so the original did not teleport to Mars at all.
  8. Standard member apathist
    looking for loot
    29 Jul '16 22:41
    Quantum teleportation transmits quantum information (and doesn't transmit matter/energy) but its interesting that it involves the "no-cloning" theorem - it is impossible to make copies using the transmitted information.
  9. 30 Jul '16 13:12
    Originally posted by apathist
    Teleporting humans is not a copying operation.
    Yes, it is. And the description in your OP quite clears states that it is.

    The op shows that copying is not sufficient for the teleportation of people.
    It does no such thing. It merely states (wrongly) that it is not sufficient without giving any reasoning.

    Electronic communication is not teleportation.
    It is essentially the same thing.

    In the second experiment, the original is unchanged. The copies are built on Mars. The original is not one of the copies.
    As long as it is indistinguishable from the others, then there is no reason to call it 'the original'. The problem is you are assigning special status to position - yet simultaneously claiming that there can be an identical entity at a different position. Make your mind up.

    Since the information sent in the first experiment would be the same information sent in the second experiment, we can see that only copies are built on mars, and so the original did not teleport to Mars at all.
    If information about position was not sent and not replicated then it is either not a true copy or position is not required for identity.
  10. Standard member apathist
    looking for loot
    02 Aug '16 23:55 / 1 edit
    Originally posted by twhitehead
    Yes, it is. And the description in your OP quite clears states that it is.

    The thought experiment description does not state that a teleportation occurred.

    It does no such thing. It merely states (wrongly) that it is not sufficient without giving any reasoning.
    It gave reasoning. In the second experiment, since the person using the (so-called!) teleporter remains unchanged on earth, it is clear he didn't teleport to mars. And since the information sent is identical in both experiments, it follows that no teleportation occurred in the first experiment.

    It is essentially the same thing.
    Electronic communication is not teleportation.

    As long as it is indistinguishable from the others, then there is no reason to call it 'the original'.
    Not true. I guess you think that a reductive physical examination is the only tool science is allowed to use.

    There is plenty of reason to call the original "the original".

    I gotta run, please think about stuff like lab notes, eyewitness reports, video evidence, and above all: the concept of timeline, lifeline or worldline.
  11. Standard member apathist
    looking for loot
    10 Aug '16 22:52
    So tw's idea is without merit. In experiment 2, the user on earth remains the original. In both experiments, only copies of the original are made and no teleportation occurs.

    Experiment #3 is like the Star Trek teleporter, where the entire body of the user is transformed from matter to energy that is 'beamed' to mars and reconstructed per the familiar information that is also sent - this is the same information that we saw in the first two experiments.

    Would the person using this device actually teleport to mars? Why or why not?