News Qubit Teleportation Paves the Way for Galaxy-Spanning Communications

Apr 1, 2020
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Quantum physics and general relativity don't currently mesh, so it is possible in the world of QP that information can travel faster than the speed of light because it's governed by a different set of laws.
 
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TJ Hooker

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Quantum physics and general relativity don't currently mesh, so it is possible in the world of QP that information can travel faster than the speed of light because it's governed by a different set of laws.
Nope, you still can't have faster than light communication even with quantum effects like entanglement. In the case of this article, they still needed a classical channel to transfer information between the two nodes. Only once the information has passed through that classical channel (which is limited by the speed of light), can the quantum teleportation be performed. The result being presented isn't that they can transmit information faster than light, it's that they are able to transmit data over a quantum 'channel' with higher fidelity than would have been possible over a classical channel.
 
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May 26, 2022
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Nope, you still can't have faster than light communication even with quantum effects like entanglement. In the case of this article, they still needed a classical channel to transfer information between the two nodes. Only once the information has passed through that classical channel (which is limited by the speed of light), can the quantum teleportation be performed. The result being presented isn't that they can transmit information faster than light, it's that they are able to transmit data over a quantum 'channel' with higher fidelity than would have been possible over a classical channel.
Incorrect. You are confused about what it means to "travel" faster than the speed of light. Information can most definitely get from point A in the universe to point B in the universe faster than it would take light to conventionally travel between those two points. One such way is via a wormhole.

"Traveling" at the speed of light means that the "thing" passes through all points in space between points A and B. In the case of quantum entanglement, the information never actually travels at all. There is no "faster than light" aspect to quantum entanglement. It simply happens instantaneously without any travel.

If you want to consider the "travel" aspect of it, the "traveling" happens when the two entangled items are separated by distance. You are correct in that the transceivers cannot travel faster than the speed of light apart from each other. Once they do, however, the information no longer actually travels anywhere.

I'm not going to waste time trying to convince you about the science behind it. Even Einstein didn't fully grasp spooky action at a distance. We don't understand it well enough to make use of it yet, so there is no point in you trying to argue that it's impossible. Just because we haven't proven we can do it doesn't mean we can't.
 

NinoPino

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Incorrect. You are confused about what it means to "travel" faster than the speed of light. Information can most definitely get from point A in the universe to point B in the universe faster than it would take light to conventionally travel between those two points. One such way is via a wormhole.

"Traveling" at the speed of light means that the "thing" passes through all points in space between points A and B. In the case of quantum entanglement, the information never actually travels at all. There is no "faster than light" aspect to quantum entanglement. It simply happens instantaneously without any travel.

If you want to consider the "travel" aspect of it, the "traveling" happens when the two entangled items are separated by distance. You are correct in that the transceivers cannot travel faster than the speed of light apart from each other. Once they do, however, the information no longer actually travels anywhere.

I'm not going to waste time trying to convince you about the science behind it. Even Einstein didn't fully grasp spooky action at a distance. We don't understand it well enough to make use of it yet, so there is no point in you trying to argue that it's impossible. Just because we haven't proven we can do it doesn't mean we can't.

Tj Hooker is not confused at all.
If you have two entangled photons, and you want to use this system to transfer information, let's say at a light year of distance, the first thing to do is to create the entangled system here on earth, than transfer one particle to the destination system. The transfer of the particle, in this case a photon, must obey relativity, so you need a year to transfer the information and only after that you can leverage the entanglement.
Moreover, there is no way to change the state of the components of the entangled system, you can only read the state and do collapse the "wave function".
About the "spooky distant action", Einstein is not wrong. Two entangled particles should be intended as an unique entity, and not as two distinct particles, so there is no real "distant action" .
 
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Tj Hooker is not confused at all.
If you have two entangled photons, and you want to use this system to transfer information, let's say at a light year of distance, the first thing to do is to create the entangled system here on earth, than transfer one particle to the destination system. The transfer of the particle, in this case a photon, must obey relativity, so you need a year to transfer the information and only after that you can leverage the entanglement.
Moreover, there is no way to change the state of the components of the entangled system, you can only read the state and do collapse the "wave function".
About the "spooky distant action", Einstein is not wrong. Two entangled particles should be intended as an unique entity, and not as two distinct particles, so there is no real "distant action" .
Wrong. That's not how a qubit works. You don't make a qubit, move it, then make a new one. Once the technology is perfected, the two devices need to be separated only once. Then, the state of one is immediately reflected in the other. You're confusing the quantum transport of keys over fiber optics with quantum computing qubits. I know it's a lot to try to follow, so I don't fault you for not understanding it.

Once two entangled communications devices are separated by 22 light years, the new data no longer has to travel at all. It's already there. You have Qa1 entangled with Qa2 and Qb1 entangled with Qb2. Qa is altered on Earth and read on the other planet. Qb is altered on the other planet and read on Earth. The speed of light is no longer involved in the equation. The states of the qubits change instantaneously. There is no "travel" of the information. It's simply there.

Quantum physics is confusing. That's why Einstein's theory breaks down at that level. We don't completely understand it all yet, though things like wormholes still work. The data doesn't travel through the universe. It traverses a quantum tunnel that is not bound by relativity.
 

edzieba

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Wrong. That's not how a qubit works. You don't make a qubit, move it, then make a new one. Once the technology is perfected, the two devices need to be separated only once. Then, the state of one is immediately reflected in the other. You're confusing the quantum transport of keys over fiber optics with quantum computing qubits. I know it's a lot to try to follow, so I don't fault you for not understanding it.

Once two entangled communications devices are separated by 22 light years, the new data no longer has to travel at all. It's already there. You have Qa1 entangled with Qa2 and Qb1 entangled with Qb2. Qa is altered on Earth and read on the other planet. Qb is altered on the other planet and read on Earth. The speed of light is no longer involved in the equation. The states of the qubits change instantaneously. There is no "travel" of the information. It's simply there.

Quantum physics is confusing. That's why Einstein's theory breaks down at that level. We don't completely understand it all yet, though things like wormholes still work. The data doesn't travel through the universe. It traverses a quantum tunnel that is not bound by relativity.
No, you're wrong here. Regardless of the distance you separate your entangled pair by, you cannot transmit information superluminally using those pairs along.
The core issue is that you cannot cannot read the complimentary state without breaking the entanglement, and you cannot influence the entangled state (the bolded part of your post is the error). You can guarantee that Qa1 != Qa2, but you cannot set Qa1 or Qa2 to be a desired outcome. The Earthbound end can read Qa1 and see that it is "1", and know that Qa2 is therefore "0", but have no way to 'tell' Qa1 to be "1" or "0", that's down a random probability. In order to communicate with the remote end,

The core premise of the article also demonstrates this fundamental misunderstanding of quantum entanglement. You can use entanglement for eavesdropping-resistant cryptography, but you still need a classical transmission path in order to use the quantum path. The linked paper is nothing to do with superluminal data transmission in the slightest! Instead, it's a paper on how to pass superposition states via intermediaries.
 
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No, you're wrong here. Regardless of the distance you separate your entangled pair by, you cannot transmit information superluminally using those pairs along.
The core issue is that you cannot cannot read the complimentary state without breaking the entanglement, and you cannot influence the entangled state (the bolded part of your post is the error). You can guarantee that Qa1 != Qa2, but you cannot set Qa1 or Qa2 to be a desired outcome. The Earthbound end can read Qa1 and see that it is "1", and know that Qa2 is therefore "0", but have no way to 'tell' Qa1 to be "1" or "0", that's down a random probability. In order to communicate with the remote end,

The core premise of the article also demonstrates this fundamental misunderstanding of quantum entanglement. You can use entanglement for eavesdropping-resistant cryptography, but you still need a classical transmission path in order to use the quantum path. The linked paper is nothing to do with superluminal data transmission in the slightest! Instead, it's a paper on how to pass superposition states via intermediaries.

Correct. This entire article is a hot mess that needs to be retracted.


https://arxiv.org/pdf/2101.04427.pdf
Quantum Internet- Applications, Functionalities, Enabling Technologies, Challenges, and Research Directions
Using entanglement for communication in technical applications is not clear, because entanglement itself does not allow information transmission. However, it can help to build a virtual secure channel or a cryptographic channel.
https://en.wikipedia.org/wiki/Quantum_teleportation
Quantum teleportation is a technique for transferring quantum information from a sender at one location to a receiver some distance away. While teleportation is commonly portrayed in science fiction as a means to transfer physical objects from one location to the next, quantum teleportation only transfers quantum information. The sender does not have to know the particular quantum state being transferred. Moreover, the location of the recipient can be unknown, but classical information needs to be sent from sender to receiver to complete the teleportation. Because classical information needs to be sent, teleportation can not occur faster than the speed of light.
 
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May 26, 2022
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You're contradicting yourself in your comment. Read what you yourself posted regarding quantum teleportation. I'll post the relevant bit:

"Quantum teleportation is a technique for transferring quantum information from a sender at one location to a receiver some distance away."

Hence, information can be transferred using quantum teleportation. Which is exactly what the article is about. No retraction needed.
Let's get real here.
Your entire article was about talking instantly across the galaxy using QM technology that you obviously didn't take the time to investigate the actual details of how it actually works.

If you want to write science fiction as an extrapolation of the nature article, that's fine but it should be labeled as such.
 
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gg83

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Information cannot travel faster than the speed of light, unfortunately. But a quantum Internet is promising for security and privacy reasons.
But they said entanglement responses are instantaneous even at great distances. If the 2 entangled particles were 22 lights years apart, it would take 22 years to see a change from one to the other? It's wacky
 
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But they said entanglement responses are instantaneous even at great distances. If the 2 entangled particles were 22 lights years apart, it would take 22 years to see a change from one to the other? It's wacky

Let's make it simple. Quantum teleportation/entanglement is not FTL.

https://www.forbes.com/sites/starts...ommunicate-faster-than-light/?sh=6754b2144d5d

As quantum physicist Chad Orzel has written, there is a big difference between making a measurement (where the entanglement between pairs is maintained) and forcing a particular result — which itself is a change of state — followed by a measurement (where the entanglement is not maintained). If you want to control, rather than simply measure, the state of a quantum particle, you'll lose your knowledge of the full state of the combined system as soon as you make that change-of-state operation happen.

Quantum entanglement can only be used to gain information about one component of a quantum system by measuring the other component so long as the entanglement remains intact. What you cannot do is create information at one end of an entangled system and somehow send it over to the other end. If you could somehow make identical copies of your quantum state, faster-than-light communication would be possible after all, but this, too, is forbidden by the laws of physics.

 
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But they said entanglement responses are instantaneous even at great distances. If the 2 entangled particles were 22 lights years apart, it would take 22 years to see a change from one to the other? It's wacky

No, that change happens instantly, but that still doesn't let you transmit information faster than the speed of light. You can't force the state of an entangled particle or view the state of an entangled particle without breaking entanglement.
 

NinoPino

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Once two entangled communications devices are separated by 22 light years, the new data no longer has to travel at all. It's already there. You have Qa1 entangled with Qa2 and Qb1 entangled with Qb2. Qa is altered on Earth and read on the other planet. Qb is altered on the other planet and read on Earth. The speed of light is no longer involved in the equation. The states of the qubits change instantaneously. There is no "travel" of the information. It's simply there.
As said from others in this thread, you cannot change the state of an entangled system, and you also can read it only once. Any observation breaks the entanglement.
Add that any interaction with other particles, like elecrons, photons, etc. do collapse the system and breaks the entanglement. Think how difficult is to send a system at a distance like this. 22 lightyears of distance may need something like 220 years at 10% the speed of light (impossible actually). During all this time the quantum system must not interact with ANY particle, also the intergalactic radiation, the spaceship, etc... simply impossible.
Quantum physics is confusing. That's why Einstein's theory breaks down at that level.
Till now, relativity have never failed. No info can be sent exceeding speed of light.
We don't completely understand it all yet, though things like wormholes still work. The data doesn't travel through the universe. It traverses a quantum tunnel that is not bound by relativity.
This is science fiction, not physics.
 
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