Non locality of quantum mechanics

In summary, the conversation discussed the possibility of a local hidden variable theory explanation for Bell's theorem, in which the outcomes of measurements on entangled particles are initially random but memories are modified to remember a particular correlation. However, this theory would require giving up on realism and may not be realistic. Other theories suggest that the Euclidean-like topology of space could be abandoned, and that entangled particles are connected by wormholes or strings in higher dimensions. Ultimately, there is no proven explanation for Bell's theorem or quantum mechanics, and all interpretations are speculative.
  • #1
entropy15
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0
Can we have a local hidden variable theory explanation for Bells theorem?

The outcomes of the mesurement (measuring the electron spin of an entangled electron pair as Red or Green) can be random initially without any correlation at all.

But by the time we compare the results of the two measurements, our memories could be modified such that we remember having made a particular of measurements which had correlation.

Would not such a explanation get rid of the non locality of quantum mechanics?
will have to give up our idea of a consistent memory for this.
 
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  • #2
will have to give up our idea of a consistent memory for this.
That means, this theory will be non-realistic. This is indeed a possible interpretation of the Bell theorem.

The Bell theorem says that you can not have all of these at once:
- realism
- locality
- casuality
- Euclidean-like topology of space

You must sacrifice at least one of these. You've decided to give up on realism. That is one possible explanation.
 
  • #3
entropy15 said:
Would not such a explanation get rid of the non locality of quantum mechanics?
will have to give up our idea of a consistent memory for this.

You would have to give up a lot more than just a consistent memory. The detector could, for example, record its findings by drilling a hole in a piece of hardened steel whenever it makes a spin-up measurement; we then could bring the two pieces of steel together in a machine that sounds a loud alarm if two holes ever line up.
 
  • #4
haael said:
- Euclidean-like topology of space

How can it be explained by abondoning Euclidean-like topology of space?
 
  • #5
You would have to give up a lot more than just a consistent memory. The detector could, for example, record its findings by drilling a hole in a piece of hardened steel whenever it makes a spin-up measurement; we then could bring the two pieces of steel together in a machine that sounds a loud alarm if two holes ever line up.
If I understand entropy15's intention well, then he thinks of a theory where distant regions remain in some kind of superposition until they meet, when they adjust themselves to satisfy the Bell theorem.
That means, two distant observers (or two distant steel bars) that record two distant experiments with entangled particles, don't have a fully defined state until they meet. Then, their memories become defined or rewritten.

How can it be explained by abondoning Euclidean-like topology of space?
Space on the fundamental level could for example be filled with lots of tiny wormholes that connect distant regions. These wormholes could transfer information between entangled particles.
Similar theory states that entangled particles are connected by some kind of string in higher dimension, which means that actually they are not that far away and communication between them is not superluminal.
 
  • #6
haael said:
If I understand entropy15's intention well, then he thinks of a theory where distant regions remain in some kind of superposition until they meet, when they adjust themselves to satisfy the Bell theorem.

don't have a fully defined state until they meet. Then, their memories become defined or rewritten.

.
Thats what I had in my mind. But is it not possible that even before they meet, they have a fully defined state. After they meet they readjust themselves so as to satisfy Bells theorem.

After all, our past is stored in our present memories. So the present memory can be changed so that we remember things differently.
 
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  • #7
entropy15 said:
Thats what I had in my mind. But is it not possible that even before they meet, they have a fully defined state. After they meet they readjust themselves so as to satisfy Bells theorem.

After all, our past is stored in our present memories. So the present memory can be changed so that we remember things differently.

you refer to a fundamental principle of symmetry (present at the emision of photons pairs), each photon "knows" it orientation (spin mode).going to that, slowly but going (studying pair by pair)

http://jqi.umd.edu/news/photons-la-mode
http://pra.aps.org/abstract/PRA/v88/i1/e013822

"For instance, to study a pair of entangled photons (created by shooting light into a special crystal where one photon is converted into a pair of secondary, related photons) detection efficiency is all important; and folded into that detection efficiency is a requirement that the arrival of each of the daughter photons be matched to the arrival of the other daughter photon. In addition to this temporal alignment, the spatial alignment of detectors, (each oriented at a specific angle respect to the beamline) must be exquisite. To correct for any type of less-than-perfect alignment, it is necessary to know how many different light modes are arriving at the detector"
"and those that emit pairs of entangled photons---where the quantum relation between the two photons is exactly right"
----
http://arxiv.org/abs/1305.5708.
 
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  • #8
But is it not possible that even before they meet, they have a fully defined state.
Well, anything is possible. I know as much as you. No QM interpretation has been proven, nor even any of it make any experimental predictions.

You ask if the state before meeting is undefined, or is it defined but rewritten. Well, what is the difference? If both these views yield the same experimental results, then they are the same. Besides, we don't have any way to prove the existence of alternative histories, since they are already gone when we seek for them.

Let me state it once again: we don't have any explanation for Bell's theorem or any interpretation for QM that is any better than others. For now, we could speculate of anything.
 

What is the non locality of quantum mechanics?

The non locality of quantum mechanics refers to the concept that particles can be connected or entangled in a way that allows them to affect each other instantaneously, regardless of the distance between them. This is in contrast to classical mechanics, where the effects of one particle on another are limited by the speed of light.

How does non locality work in quantum mechanics?

In quantum mechanics, particles can become entangled through interactions, such as collisions or emissions. This means that their properties, such as spin or position, become correlated. When one particle's property is measured, it instantaneously affects the property of the other particle, even if they are separated by great distances.

What are the implications of non locality in quantum mechanics?

The implications of non locality in quantum mechanics are still being studied and debated. Some interpretations suggest that it challenges our understanding of causality and the nature of reality. It also has potential applications in quantum computing and communication.

Is non locality a proven phenomenon in quantum mechanics?

While non locality has been observed in various experiments, it is still a highly debated topic in the scientific community. Some interpretations suggest that it is a fundamental aspect of quantum mechanics, while others propose alternative explanations for the observed phenomena.

How does non locality relate to Einstein's theory of relativity?

The concept of non locality in quantum mechanics contradicts the principle of locality in Einstein's theory of relativity, which states that information cannot travel faster than the speed of light. This has led to ongoing discussions and debates about the compatibility of these two theories.

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