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entropy1
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If we assume there is no counterfactual definiteness, would that mean that measurements on entangled particles needn't be correlated, for if you don't compare the results, you just don't know if they do?
So, CFD has necessarily to do with non-commutation?DrChinese said:Counterfactual definiteness (CFD) is really about unperformed measurements. If you measure momentum on A and position on B: you cannot really talk about A's position and B's momentum at the same point in time unless there exists CFD. Classically, objects do not have non-commuting measurement operations. Quantum objects do.
entropy1 said:Because, I was aiming at eternal separation in spacetime of two measurements that were performed. The thing with that would then be that Alice would never know whether Bob actually did carry out a measurement.
I mean forever separated in the future. (after preparation)Markus Hanke said:If the two particles are eternally separated ( i.e. in the past and in the future ), then I don't see how you can have entanglement - not only will it be impossible to verify the correlation, but the entanglement cannot exist in the first place, since its creation requires an initial interaction between the particles.
entropy1 said:I mean forever separated in the future. (after preparation)
entropy1 said:Are things of which we don't have information relevant anyway?
Markus Hanke said:If the two particles are eternally separated ( i.e. in the past and in the future ), then I don't see how you can have entanglement - not only will it be impossible to verify the correlation, but the entanglement cannot exist in the first place, since its creation requires an initial interaction between the particles.
Markus Hanke said:That is why I think there should be some notion of observer-dependence here, although I don't know what it would formally ( = mathematically ) look like.
DrChinese said:Not so fast, grasshopper.
Markus Hanke said:Lol, just as I thought I had the whole EPR-entanglement thing hammered down, someone comes along and throws a spanner in my mental works I am going to have to digest your last three posts, and definitely do a bit more reading on this subject, as I wasn't aware of the phenomena you have mentioned. The learning never ends !
Forward and backward in time? (space?)DrChinese said:but requires forward and backward effect propagation to explain anything.
entropy1 said:Forward and backward in time? (space?)
Why should not do soentropy1 said:If we assume there is no counterfactual definiteness, would that mean that measurements on entangled particles needn't be correlated, for if you don't compare the results, you just don't know if they do?
Because there is word lately about forward and backward 'influence/causality' in time on quantum level! That might mean that what happens later (i.e. the bringing together of information to establish the correlation) has some interaction with what happens earlier (i.e. the preparation of the entangled particles). In that case, the future might be just as important as the past. I image a quantum wave (e.g. a state) propagating forward in time and another one backward. (of course this is heavily simplified)Cherye Norris said:Why should not do so
bluecap said:Can a mentor confirm if what entropy said above was true.. that the bringing together of information to establish the correlation is what created the correlation in entanglement (like some time reversed process)? For instance. Alice and Bob located 14 billion light years away took 14 billion years to travel for classical comparison.. then that bringing togethe of information affects the past? but how could it be?
I don't like that idea; it doesn't seem to fit with entanglement. I rather like to think in terms of 'resonance', wherein future probability waves interfere with past ones in a way that due to slight variations (HUP/quantum fluctuations) in the combination of influences from the present as well as the future, the 'outcome' of the both present and future influences reinforce ('resonate') to some outcome at some point. This means that causal influences of the future cancel with causal influences of the present (past), with a net undetectable causation. This seems to correspond most (but not entirely) with TI.DrChinese said:[..]some people call it Retrocausal.
entropy1 said:future probability waves interfere with past ones in a way that due to slight variations (HUP/quantum fluctuations) in the combination of influences from the present as well as the future, the 'outcome' of the both present and future influences reinforce ('resonate') to some outcome at some point (eg. as in a [negative] well).
It is my own view that I find partly supported by TI. It is an interpretation. QM has already been confirmed. However, TI produces drastically more simple math, I think.Grinkle said:I think I saw that episode of STtNG. ;-)
Is this discussion based on both math and experimental observation? Its very interesting, but its also pretty out there to this lay person.
Counterfactual definiteness is a concept in quantum mechanics that states that for any given physical system, there is a definite set of properties that exist regardless of whether they are observed or measured. This means that even if we do not observe a system, its properties still exist in a definite and well-defined state.
Counterfactual definiteness is closely related to the concept of correlation in that it implies that there is a direct cause-and-effect relationship between two correlated systems. In other words, the properties of one system can be used to predict the properties of the other system, even if they are not directly interacting.
Counterfactual definiteness is an important concept in quantum mechanics because it helps us to understand the behavior of physical systems and make predictions about their properties. It also plays a crucial role in various experiments and measurements, and is a fundamental concept in the study of quantum mechanics.
The concept of counterfactual definiteness is still a topic of debate in the scientific community. While it is a fundamental assumption in many theories in quantum mechanics, there is currently no experimental evidence that definitively proves its existence. However, many scientists continue to study and research this concept in order to gain a better understanding of the behavior of physical systems.
While counterfactual definiteness is a concept that is primarily used in the field of quantum mechanics, it can have some applications in everyday life. For example, it can help us to understand how seemingly unrelated events can be connected and how certain actions can have predictable consequences. However, it is important to note that this concept is currently still being studied and its applicability to everyday life is still being explored.