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Re:Best attempts so far to skin Schrödinger’s cat (2016) by Tade0 on Saturday September 30, 2017 @04:23AM (#15371877)
This is what I hate about the popular understanding of the Copenhagen interpretation.

Bohr's original idea was that until there's some interaction it's pointless to assign a specific state - you can only talk about certain probabilities.

Schrodinger's cat is not both alive and dead. We know nothing about its current state, only how probable certain outcomes are.

Re:Best attempts so far to skin Schrödinger’s cat (2016) by jon_richards on Saturday September 30, 2017 @07:30AM (#15372350)
>Schrödinger described how one could, in principle, create a superposition in a large-scale system by making it dependent on a quantum particle that was in a superposition. He proposed a scenario with a cat in a locked steel chamber, wherein the cat's life or death depended on the state of a radioactive atom, whether it had decayed and emitted radiation or not. According to Schrödinger, the Copenhagen interpretation implies that the cat remains both alive and dead until the state is observed. Schrödinger did not wish to promote the idea of dead-and-alive cats as a serious possibility; on the contrary, he intended the example to illustrate the absurdity of the existing view of quantum mechanics. However, since Schrödinger's time, other interpretations of the mathematics of quantum mechanics have been advanced by physicists, some of which regard the "alive and dead" cat superposition as quite real.

I was taught that Schrödinger's Cat was conceived of as intentionally absurd, but that physicists loved it because it pointed out how absurd physics was being. As the other comment said, its not just that a photon might have gone through either slit, it provably went through both.

Re:Best attempts so far to skin Schrödinger’s cat (2016) by frede on Saturday September 30, 2017 @07:13AM (#15372296)
The thing about quantum theory is that it's not just about propabilities. The double-slit experiment, for example, cannot be explained by adding propabilities alone. Instead the wave function gets added, with the phase considered. This is why an unobserved quantum state is more than a classical state hidden in a box and why we get results that seem paradox.
Re:Best attempts so far to skin Schrödinger’s cat (2016) by coldtea on Saturday September 30, 2017 @08:33AM (#15372573)
>Schrodinger's cat is not both alive and dead. We know nothing about its current state, only how probable certain outcomes are

That's the case with any cat we throw in a box and ask somebody to kill it or not based on a dice, and then we visit the place where the box is and open it...

In other words, the cat is in a certain state, but we merely don't know which.

But this doesn't capture what the Schrodinger experiment is supposed to show. Such an case wouldn't need the experimental apparatus Schrodinger describes either.

The core idea of the experiment is that quantum uncertainty is not just of the "we just don't know yet" kind, but of the fundamental "reality is inherently mixed-up and uncertain / many things actually hold at the same time until observed" nature.

The purpose of the Schrodinger's thought experiment then is to show how this fundamental quantum uncertainty (i.e. not mere not knowing: actual "fuzzy" reality) "pollutes" the macro world (in this case, a cat).

The quantum-based mechanism that releases the poison, is his trick to transfer the uncertainty of the quantum state into the macro world (the box with the cat). (Funnily, Schrodinger's purpose was to discredit this).

Those that believe it's clear that "the cat is in one state or another, we just don't know which", haven't understood the problem.

Re:Best attempts so far to skin Schrödinger’s cat (2016) by n4r9 on Saturday September 30, 2017 @01:01PM (#15373791)
You've slightly misinterpreted the point of the previous post, or have at least overlaid some assumptions.

You're arguing against what one might call an objective Bayesianism stance. That is to say that our probabilities reflect our inadequate information concerning an objective (classical) state of reality for the cat.

However the phrase

> Schrodinger's cat is not both alive and dead. We know nothing about its current state, only how probable certain outcomes are

suggests a perspective in which there is not an objective (classical) state of reality for the cat. Rather, probabilities might be seen as subjective assertions about the outcome of interactions with the system. It is meaningless to talk about the cat being dead or alive before looking. This is closer to what one might call a subjective Bayesian stance.

Re:Best attempts so far to skin Schrödinger’s cat (2016) by coldtea on Saturday September 30, 2017 @07:04PM (#15375441)
>It is meaningless to talk about the cat being dead or alive before looking. This is closer to what one might call a subjective Bayesian stance.

In actual classical reality, it's not at all meaningless to ask whether the cat is "dead or alive before looking". It might be uncertain, but it's not meaningless.

One might say "I think it's alive" and another "dead" -- and they have a chance to be right even before opening the box -- we'll just need to open it and see which was right ALL ALONG.

In quantum physics, on the other hand, in most interpretations, none of them is right before opening the box. If one says "the cat must be dead", and we open the box and the cat is indeed found dead, that person, wasn't right all along. He only became right upon the opening.

That's the whole paradox that Schrodinger tried to point out as an absurd result of quantum mechanics -- but which nonetheless is accepted by physicists not as a counter-example against QM, but as something still paradoxical that actually illustrates a key point about QM.

Re:Best attempts so far to skin Schrödinger’s cat (2016) by Tade0 on Saturday September 30, 2017 @02:38PM (#15374329)
You've described my position in a way I couldn't dream to reproduce, thank you.