All Questions
Tagged with faster-than-light quantum-information
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How do non-local correlations occur in QM without a cause? [closed]
The Copenhagen interpretation of QM ultimately amounts to asserting that non-local correlations occur without a cause since that cause would involve propagation of information faster than the speed ...
user398827
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What are the implications of the EPR bridge information metric being invariant under all conditions, including distance in this universe?
What if the reason why instantaneous state information is able be transmitted between entangled particles through an EPR bridge is that the metric that this is conveyed in is invariant under all ...
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Can entanglement witnesses on GHZ states with $n > 2$ violate the non-communication theorem?
In experiments involving entangled photons, measuring entanglement in systems with more than two particles ($n > 2$) often employs one photon as a herald to distinguish signal photons from noise. ...
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Simultaneous measurements of two entangled particles [duplicate]
Experimental evidence reject the local hidden variable theory, so let's say quantum mechanics is right and the wave function does instantaneously collapse upon measurement.
Suppose we have two ...
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What is the state of an entangled photon after its twin is absorbed?
Let's two photons are entangled in polarization after a laser beam passes through a Betha Barium Borate crystal. They take different paths and one of them (1) is absorbed in a black sheet. What is the ...
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Is it possible to test if the entangled twin of a particle has already been measured or not? [duplicate]
Suppose a pair of entangled particles having opposite up/down spins are produced on Earth.
These two particles are then separated, one remaining on Earth, and the entangled pair being brought by ...
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Does it matter when we measure the spin of the other entangled particle?
Let's say, we have 2 entangled particles: A and B which are a light-year away from each other.
We know if we measure the spin of particle A, we can be certain the spin of particle B will be in the ...
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A simple counter-example to the no-communication theorem? [duplicate]
Let's say Alice and Bob would like to communicate through entangled qubits. They have a machine that generates qubits in the state
$$
| \psi \rangle = \alpha | 0 0 \rangle + \beta | 1 1 \rangle .
$$
...
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Isn't There A Much Simpler Way To Explain Why Quantum Entaglement At Distance Isn't Utile - That Spins Already Exist & React To Detection Predictably? [closed]
Tell me if this concept works for explaining in a much simpler way, why purposeful entanglement outcomes like FTL communication cannot work - and without relying on complex analyses of 'spooky action',...
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Does anything "break" in physics if you allow for instant (faster-than-light) communication?
Assume that two entities, Alice and Bob, can communicate thoughts literally instantly. If Bob thinks "Alice, I want you to jump", then Alice (many, many light-years away) will know that ...
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Can information travel faster than speed of light in this situation?
I know the answer is no but I have a thought experiment that seem to be violating that. Imagine two persons living on two different planets namely A and C which are 10 light years apart. There is a ...
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Does entanglement mean that information travels faster than light? [duplicate]
Every time in physics (in popsci) I hear that it is not possible to travel faster than light, as this would cause many problems that I do not understand.
On the other side, in Quantum Computing (in ...
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Does the collapse of the wave function happen immediately everywhere?
It is usually taught that when we measure some measurable value the wave function collapses immediately everywhere. This idea sounds like a simplification of some more complicated mechanism.
Are ...
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Faster than light communication protocol via GHZ-state
I had a chat with a guy recently who claimed that multipartite entanglement might actually be used for superluminal communication, and his argument is very simple.
Suppose that 2 observers (Alice and ...
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How can information be communicated with entanglement? [closed]
Forgive my overly simplistic view of this. But I have been wondering this for years. Any insight would be greatly appreciated.
So imagine you have two entangled particles, and they are separated and ...
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