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Researchers quantum teleport particle of light six kilometres

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Re: Researchers quantum teleport particle of light six kilometres

#121
Forgive my ignorance as I'm a software engineer and not a physicist. But does this means that in the future FTL communication will be possible. Every time I work with networking one thing always springs to mind. That is that the speed of light is a limiting factor. Will this mean that in the future latency issues will be a thing of the past?

http://www.stuartcheshire.org/rants/latency.html

Re: Researchers quantum teleport particle of light six kilometres

#122
post #60

Earlier quoted context omitted.

Is "measurement" or "observation" a simplified term for a complex process? It can't be as simple as a human "looking" at something since there's nothing special about humans (that I know of). I really wish I had the time and capability to understood how quantum entanglement really works. It seems a lot like magic if you take the layman explanations at face value.

To "observe" can mean any sort of interaction between the particle and a larger, connected physical system. To observe something, you have to have a physical interaction with it (it is hit by a photon of light which then hits your eyes, to use the most basic example) and so its quantum state decoheres into a particular state. Most scientists are fine with the idea that it doesn't matter if the larger physical system…

I'm a lay person when it comes to QM: I get my information from Brian Greene's excellent books. I kind of think it is going too far to say that it's pseudoscience and poor metaphors that make it seem like magic. Readers of the popular scientific accounts learn that the various slit experiments with partial observation etc show that these subatomic particles behave like spreading waves of probability until they are observed at which point it's like a sample is taken from the probability distribution. That seems very magical to me and has done to many scientists over the last century, right?

Re: Researchers quantum teleport particle of light six kilometres

#123

Not quite as impressive when you know, and if you don't you should before opening this link, that "quantum teleportation" is not teleportation. It was a cool-sounding name at the time, but has nothing to do with sci-fi style teleportation: nothing disappears from one place and then shows up in another. "Quantum teleportation" is a process of information duplication using particles that already exist, and have been po…

It's easier to think these as random number generators seeded with same value, taken six kilometers apart from each other, and then fetching values from them. No data is transmitted when fetching values from these.

No, you're thinking about quantum entanglement.

Re: Researchers quantum teleport particle of light six kilometres

#124

Forgive my ignorance as I'm a software engineer and not a physicist. But does this means that in the future FTL communication will be possible. Every time I work with networking one thing always springs to mind. That is that the speed of light is a limiting factor. Will this mean that in the future latency issues will be a thing of the past? http://www.stuartcheshire.org/rants/latency.html

Quantum teleportation can't be used to send data faster than the speed of light, more accurately understood here as the speed of causality. As far as I'm aware, there's really no hypothetical way to violate the speed of causality.

Re: Researchers quantum teleport particle of light six kilometres

#125

Earlier quoted context omitted.

It's easier to think these as random number generators seeded with same value, taken six kilometers apart from each other, and then fetching values from them. No data is transmitted when fetching values from these.

No, you're thinking about quantum entanglement.

Yes, and as others pointed out below, this is essentially entanglement.

Re: Researchers quantum teleport particle of light six kilometres

#126

Not quite as impressive when you know, and if you don't you should before opening this link, that "quantum teleportation" is not teleportation. It was a cool-sounding name at the time, but has nothing to do with sci-fi style teleportation: nothing disappears from one place and then shows up in another. "Quantum teleportation" is a process of information duplication using particles that already exist, and have been po…

It's easier to think these as random number generators seeded with same value, taken six kilometers apart from each other, and then fetching values from them. No data is transmitted when fetching values from these.

Are we witnessing the first steps towards interplanetary turn-based seed driven gaming?!

Re: Researchers quantum teleport particle of light six kilometres

#127
post #63
post #60

Earlier quoted context omitted.

To "observe" can mean any sort of interaction between the particle and a larger, connected physical system. To observe something, you have to have a physical interaction with it (it is hit by a photon of light which then hits your eyes, to use the most basic example) and so its quantum state decoheres into a particular state. Most scientists are fine with the idea that it doesn't matter if the larger physical system…

>seems for just a second like a normal, intuitive process that's just been obscured through poor explanation--then you learn a little more and realize it's far more bizarre than you'd imagined. This is a great explanation of the process of learning about quantum mechanics. A good test once you start to think you have figured things out is to check how your own conceptual model deals with Bell violations or experiment…

That blew my mind the first time I read it. There's also: https://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser

Re: Researchers quantum teleport particle of light six kilometres

#128
post #54
post #3

>> Researchers teleport particle of light six kilometres I'm sure they did nothing of the sort. At best they transferred an unknown state of a photon to another photon six kilometers away, then confirmed via measuring both.

Not so fast. There is a good reason to call it quantum teleportation and not quantum facsimile. When you move matter from one place to another it moves, it's not copied. When move classical information (or state) , you can retain the original or multiply it many times. Quantum teleport demonstrates interesing aspects of quantum information that makes it work like material thing. When information (quantum state) moves…

"When you move matter from one place to another it moves, it's not copied."

Matter is not being moved here.

"There is no physical of philosophical argument differentiate between "real" teleportation and "just moving state"."

Sure there is.

Arguably - that nothing was copied or transferred in the first place and that the particle was always in a given state until it was observed.

Re: Researchers quantum teleport particle of light six kilometres

#129
post #54
post #3

>> Researchers teleport particle of light six kilometres I'm sure they did nothing of the sort. At best they transferred an unknown state of a photon to another photon six kilometers away, then confirmed via measuring both.

Not so fast. There is a good reason to call it quantum teleportation and not quantum facsimile. When you move matter from one place to another it moves, it's not copied. When move classical information (or state) , you can retain the original or multiply it many times. Quantum teleport demonstrates interesing aspects of quantum information that makes it work like material thing. When information (quantum state) moves…

"When you move matter from one place to another it moves, it's not copied."

Matter is not being moved here.

"There is no physical of philosophical argument differentiate between "real" teleportation and "just moving state"."

Sure there is.

Arguably - that nothing was copied or transferred in the first place and that the particle was always in a given state until it was observed.

Re: Researchers quantum teleport particle of light six kilometres

#130

Not quite as impressive when you know, and if you don't you should before opening this link, that "quantum teleportation" is not teleportation. It was a cool-sounding name at the time, but has nothing to do with sci-fi style teleportation: nothing disappears from one place and then shows up in another. "Quantum teleportation" is a process of information duplication using particles that already exist, and have been po…

"nothing disappears from one place and then shows up in another."

This is false. The quantum data is completely destroyed at the entry point and it shows up at the end point.

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