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Fraser
2017-Aug-01, 10:40 PM
Quantum entanglement remains one of the most challenging fields of study for modern physicists. Described by Einstein as “spooky action at a distance”, scientists have long sought to reconcile how this aspect of quantum mechanics can coexist with classical mechanics. Essentially, the fact that two particles can be connected over great distances violates the rules […]
The post Physicists Take Big Step Towards Quantum Computing and Encryption with new Experiment (https://www.universetoday.com/136648/physicists-take-step-towards-quantum-computing-encryption-new-experiment/) appeared first on Universe Today (https://www.universetoday.com).


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WaxRubiks
2017-Aug-01, 11:20 PM
maybe if information can travel faster than light in this way, perhaps physical objects could too..?
And would it also mean being able to send information back in time?

Jens
2017-Aug-02, 12:03 AM
maybe if information can travel faster than light in this way, perhaps physical objects could too..?
And would it also mean being able to send information back in time?

No, it does not follow, because it's not really the same thing. Things cannot travel faster than the speed of light. But in experiments like these, you can have two particles that are linked in some way. And when you do something to one of them, something happens to the other at the same time, as if they were the same particle being in two places at the same time. So it's not necessarily that the information is going faster than the speed of light--for some reason, the information is simultaneously existing in two places.

WaxRubiks
2017-Aug-02, 12:41 AM
the article says:

Last, but certainly not least, there is the concept of Quantum Entanglement Communications, a method that would allow us to transmit information faster than the speed of light. Imagine the possibilities for space travel and exploration if we are no longer bound by the limits of relativistic communication!

but maybe he misinterpreted the experimental results.

Jens
2017-Aug-02, 02:14 AM
but maybe he misinterpreted the experimental results.

I don't think it's a misinterpretation, but it's not saying anything different than what I was trying to say. You can imagine it like this. Suppose that you make two photons go in different directions at the speed of light, but somehow those photons are deeply connected, so that one you do something to one of them, the same thing happens to the other (as if they were really the same photon!). Then you can use that to communicate with somebody faster than the speed of light, even though the photons themselves are not traveling faster than the speed of light.

WaxRubiks
2017-Aug-02, 02:54 AM
I don't think it's a misinterpretation, but it's not saying anything different than what I was trying to say. You can imagine it like this. Suppose that you make two photons go in different directions at the speed of light, but somehow those photons are deeply connected, so that one you do something to one of them, the same thing happens to the other (as if they were really the same photon!). Then you can use that to communicate with somebody faster than the speed of light, even though the photons themselves are not traveling faster than the speed of light.

If you can send information faster than the speed of light then someone on a planet 2 light years away could communicate with us 2 years in their past(assuming instant communication) we could receive information from them, and then......and in two years, we could communicate with them instantaneously and we could give information from the present to give to the Earth people in the past, or summat like that......

Reality Check
2017-Aug-02, 04:40 AM
The "Quantum Entanglement Communications" part of the article is wrong.
Both particles start in a mixed state that connects them. The measurement of the state of one particle breaks the connection leaving the other particle in a mixed, unknown state. We can send the state of the first particle and then derive what state the second particle is without measuring it. That communication is limited by the speed of light. Thus FTL communications using entanglement is not implied by entanglement. See The Real Reasons Quantum Entanglement Doesn't Allow Faster-Than-Light Communication (https://www.forbes.com/sites/chadorzel/2016/05/04/the-real-reasons-quantum-entanglement-doesnt-allow-faster-than-light-communication/#15d6a11c3a1e) and Wikipedia Superluminal communication (https://en.wikipedia.org/wiki/Superluminal_communication#Quantum_nonlocality)

WaxRubiks
2017-Aug-02, 05:13 AM
that's what I have always read, so I was a bit surprised.