Comment on I'm good, thanks
SmoothOperator@lemmy.world 2 weeks agoUnlike the Copenhagen interpretation, it does not privilege measurement over other types of interactions between systems.
Hmm, you could say it instead privileges the subjective experience over other types of interaction. There’s no reason in principle why you couldn’t experience every “world” at the same time, in the same way a measurement could in principle return all possible results at the same time.
But you don’t. Somehow your experience of reality is above unitary time evolution, even though “you” aren’t.
bitcrafter@programming.dev 2 weeks ago
I agree completely that that the Copenhagen interpretation makes an excellent phenomenological model in simple (albeit, very common!) settings. However, the problem is that it breaks down when you consider experiments such as the “quantum eraser” (mentioned in other comments here), which causes people to tie themselves into intellectual knots because they are thinking too hard about exactly what is going on with measurement; once one deprivileges measurement so that it becomes just another kind of interaction, the seeming paradoxes disappear.
SmoothOperator@lemmy.world 2 weeks ago
Copenhagen interpretation doesn’t break down for quantum erasure. Upon measurement you collapse the total quantum state into a result where the two measurements are consistent, that’s simply what entanglement means.
The timing of experiments, and the choice of what to measure, are elements ultimately irrelevant to the above statement, as the quantum erasure experiment demonstrates.
bitcrafter@programming.dev 2 weeks ago
To clarify my imprecise language, what “breaks down” is not its ability to give the correct answer, but the ability of the conceptual framework to give a clear explanation of what is going on, because it essentially defines measurement as “you know one when you see one”, which can lead to confusion.
(However, separately, I do feel the need to point out that “entanglement” is not at all a term that is related to measurement results per se, but rather to the state of a system before you measure it. In particular, if a system is entangled, you can (in principle) disentangle it by reversing whatever process you used to entangle it so that you no longer get correlations in the measurements.)
SmoothOperator@lemmy.world 2 weeks ago
I don’t know, Many Worlds always led to more confusion than Copenhagen for me. But I suppose that’s a matter of taste since they’re equivalent.
As per the relationship between measurement and entanglement, from an empiricist viewpoint all quantum mechanical terms are related to measurement. If entanglement didn’t affect the outcome of measurements, it wouldn’t exist.
Indeed, you can disentangle an entangled system, which of course will change the outcome of measurements - that’s how you know it’s been disentangled.