Why can’t entanglement be explained by a signal?

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SUMMARY

The discussion centers on the inability to explain quantum entanglement through classical signaling mechanisms. Participants argue that while the "no signaling" theorem prevents the use of entanglement for communication, it does not rule out the possibility of particles influencing each other instantaneously. The conversation references the Stern-Gerlach experiment and the delayed choice quantum eraser as critical studies that highlight the complexities of measurement in quantum mechanics. Ultimately, the notion that particles could send signals to each other is dismissed as insufficient to explain the observed phenomena.

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TL;DR
Signals in entanglement
Why can’t entanglement be explained by a signal being sent from one measurement to the other?


When one particle is measured, it sends this information out to the other particle through some physical means (likely at crazy high speeds faster than light), and this determines the other particle’s state.

To my mind, I can’t see any evidence of this being ruled out by anywhere in physics. There is the “no signalling” theorem but that just means we can’t find a way to send information using entanglement yet, and that is only because we don’t know the measurement of one particle (whether it’ll be spin up or down) before it happens. This doesn’t mean that the particles cannot physically influence each other.

This seems to be the most simple, plausible explanation for this phenomenon. What other explanation could there be anyways?
 
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Study the Stern-Gerlach experiment in detail and tell me when the electron knows its spin had been measured.

Or, the delayed choice quantum eraser.

How does the electron know it's part of an entangled system, where its partner is and what message to send?

The idea of elementary particles being sufficiently sentient to message each other is not an option.
 
PeroK said:
Study the Stern-Gerlach experiment in detail and tell me when the electron knows its spin had been measured.

Or, the delayed choice quantum eraser.

How does the electron know it's part of an entangled system, where its partner is and what message to send?

The idea of elementary particles being sufficiently sentient to message each other is not an option.
I don’t necessarily mean the particles being sentient or the human concept of messaging.

I just mean the physical process of something, whatever it is, travelling between one area of measurement to the other, causing correlated results
 
sahashmi said:
I don’t necessarily mean the particles being sentient or the human concept of messaging.

I just mean the physical process of something, whatever it is, travelling between one area of measurement to the other, causing correlated results
If you took the time to study these experiments you'd see that there is no clear point at which a measurement of a certain quantity has taken place. Usually a quantity like spin is inferred from a final detection at some point. If that detection does not take place then the inferred measurement never happened in the first balance.

Quantum mechanical formalism explains all this. Particles messaging each other cannot.
 
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PeroK said:
If you took the time to study these experiments you'd see that there is no clear point at which a measurement of a certain quantity has taken place. Usually a quantity like spin is inferred from a final detection at some point. If that detection does not take place then the inferred measurement never happened in the first balance.

Quantum mechanical formalism explains all this. Particles messaging each other cannot.
The point is there is some final measurement outcome on one end and another on the other, even if we don’t know “when” exactly the measurement happens.

For example, there could be a non local physical wave function that collapses as soon as one is measured, which in a very fast way affects the measurement outcome of the other end (if the measurement occurs).
 
sahashmi said:
TL;DR Summary: Signals in entanglement

Why can’t entanglement be explained by a signal being sent from one measurement to the other?


When one particle is measured, it sends this information out to the other particle through some physical means (likely at crazy high speeds faster than light), and this determines the other particle’s state.

To my mind, I can’t see any evidence of this being ruled out by anywhere in physics. There is the “no signalling” theorem but that just means we can’t find a way to send information using entanglement yet, and that is only because we don’t know the measurement of one particle (whether it’ll be spin up or down) before it happens. This doesn’t mean that the particles cannot physically influence each other.

This seems to be the most simple, plausible explanation for this phenomenon. What other explanation could there be anyways?
How would you explain the fact that we don't observe this signal?
 
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sahashmi said:
TL;DR Summary: Signals in entanglement

Why can’t entanglement be explained by a signal being sent from one measurement to the other?


When one particle is measured, it sends this information out to the other particle through some physical means (likely at crazy high speeds faster than light), and this determines the other particle’s state.

To my mind, I can’t see any evidence of this being ruled out by anywhere in physics. There is the “no signalling” theorem but that just means we can’t find a way to send information using entanglement yet, and that is only because we don’t know the measurement of one particle (whether it’ll be spin up or down) before it happens. This doesn’t mean that the particles cannot physically influence each other.

This seems to be the most simple, plausible explanation for this phenomenon. What other explanation could there be anyways?
What if the two particles are measured simultaniously? Which signals, or do they both signal each other? Is the speed then infinite? Do they signal all particles in the universe or just each other? How do they know who to signal?....

How is this even an explanation! It raises many questions and answers none.
 
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@sahashmi You have already made this argument a half-dozen times in the past month. You don’t have to listen to or agree with the responses, but they aren’t going to be different when you do it yet again.

This thread is closed.
 
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