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Sustained, high-fidelity quantum teleportation

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Re: Sustained, high-fidelity quantum teleportation

#41
post #12

context: Using term teleportation makes sense in the quantum realm. No-cloning theorem in quantum physics says that it's impossible to do exact copy of unknown quantum state. But it turns out that you can teleport it when the original state is destroyed. You can't have exact `cp` command for the quantum state, only `mv`. If this makes you think linear logic, you are right.

what is non-linear logic?

Re: Sustained, high-fidelity quantum teleportation

#42
post #38
post #20

Earlier quoted context omitted.

This makes zero sense. If the information must be conveyed classically anyway, what's the point?

Great question! This gets to the heart of why quantum teleportation has any value at all. So, before QM there was already a sense in which you could teleport an object: simply measure its state perfectly and send that information to another location and have them reconstruct that state particle by particle. In principle the new system would be indistinguishable from the original system and you could claim that you've…

Very interesting. If I understand correctly, does this mean cloning is a functionally impossible task?

I've always been entertained by the paradoxes where someone is teleported ala Michael Crichton's Timeline, and is then (due to some glitch) "duplicated", leading to interesting quandaries about "who is who".

If Penrose is right about consciousness [0], this means all these fantastical paradoxes are just fantasy, right?

[0]: https://bigthink.com/paul-ratner/why-a-genius-scientist-thin...

Re: Sustained, high-fidelity quantum teleportation

#43
post #38
post #20

Earlier quoted context omitted.

This makes zero sense. If the information must be conveyed classically anyway, what's the point?

Great question! This gets to the heart of why quantum teleportation has any value at all. So, before QM there was already a sense in which you could teleport an object: simply measure its state perfectly and send that information to another location and have them reconstruct that state particle by particle. In principle the new system would be indistinguishable from the original system and you could claim that you've…

It sounds like start trek’s transporter beams may be more accurately described than we thought.

Re: Sustained, high-fidelity quantum teleportation

#44
post #38

Earlier quoted context omitted.

Great question! This gets to the heart of why quantum teleportation has any value at all. So, before QM there was already a sense in which you could teleport an object: simply measure its state perfectly and send that information to another location and have them reconstruct that state particle by particle. In principle the new system would be indistinguishable from the original system and you could claim that you've…

Very interesting. If I understand correctly, does this mean cloning is a functionally impossible task? I've always been entertained by the paradoxes where someone is teleported ala Michael Crichton's Timeline , and is then (due to some glitch) "duplicated", leading to interesting quandaries about "who is who". If Penrose is right about consciousness [0], this means all these fantastical paradoxes are just fantasy, ri…

Correct, cloning in even the simplest sense of a single particle state (let alone a whole human) is impossible in quantum mechanics.

Re: Sustained, high-fidelity quantum teleportation

#45

Earlier quoted context omitted.

This reveals my severe ignorance about quantum mechanics; but I've always wondered if entanglement could be used to transmit binary data by way of timing and presence or lack of presence of a transmission. So maybe every 1ms is a position, and either something is sent or not.

You can't. There's a theorem and everything. If there is some way to do it, QM must be wrong. https://en.m.wikipedia.org/wiki/No-communication_theorem

Thank you. For me, this clears up a long held misconception.

Re: Sustained, high-fidelity quantum teleportation

#46

Earlier quoted context omitted.

This reveals my severe ignorance about quantum mechanics; but I've always wondered if entanglement could be used to transmit binary data by way of timing and presence or lack of presence of a transmission. So maybe every 1ms is a position, and either something is sent or not.

You can't. There's a theorem and everything. If there is some way to do it, QM must be wrong. https://en.m.wikipedia.org/wiki/No-communication_theorem

Thanks for the link; I had no idea what to even search for to understand this.

Re: Sustained, high-fidelity quantum teleportation

#47

Earlier quoted context omitted.

So that could neatly solve the philosophical teleportation problem? Ie if you teleport and the original isn’t destroyed. Which one are you?

But if they destroy you and recreate you, are you still alive or die in the process?

If you're entangled before you're destroyed have you really been destroyed?

Re: Sustained, high-fidelity quantum teleportation

#49
post #12

context: Using term teleportation makes sense in the quantum realm. No-cloning theorem in quantum physics says that it's impossible to do exact copy of unknown quantum state. But it turns out that you can teleport it when the original state is destroyed. You can't have exact `cp` command for the quantum state, only `mv`. If this makes you think linear logic, you are right.

what is non-linear logic?

Non-linear logic would be regular old logic. Linear logic is logic where every operation permanently consumes its input.
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