The “dead and alive” cat myth

No, this is wrong. If the box is made of glass and you can see what's happening inside, the photons that reflect off the cat collapse the wavefunction so the cat really is alive or dead. In the case of the metal box and the completely isolated system, the cat is really in a fundamental way in a superposition of alive and dead - you can construct an experiment [1] that shows that entanglement can't be explained by local hidden variable theories.

[1]: https://en.wikipedia.org/wiki/CHSH_inequality

Nothing about this makes any sense. The cat is an analogy, the box is an analogy. Everything about that thought experiment is an analogy.

The moon is still there, even if noone looks up into the night sky. The cat is either alive or dead because it is constantly "observed." That's why there's no differnce between a glass box and a metal box. Observation in the quantum mechanical sense doesn't mean that the author has to eyeball an object. It means that the object interacts with its environment (e.g. the particles of the cat interact with each other and the particles in the air).

The analogy with statistics, that quantum mechanics is simply the evolution of "what we know" is not correct either. A superposition is much more than that. When a particle is in superposition of two states, it can interact with itself as if it was in one state and as if there was another particle in the other one (but there has never been a second particle).

If you simply assume that you "don't know" in which state it was and that it would still behave classically, you would not be able to explain the double-slit experiment. You also wouldn't be able to explain why light is slower in a dielectric. Also, physics would be way easier.

P.S.: What the hell are those little snow flakes on that website. At first I thought I was seeing stars and that I was about to pass out...

I'll just leave these here:

https://en.wikiquote.org/wiki/Talk:Richard_Feynman#.22If_you...

http://www.smbc-comics.com/comic/law-of-social-media

While I agree that the box cat is not a valid thought experiment, just dismissing quantum superposition is not a solution.

The double slit experiment (while tangential) shows that discrete events can somehow be connected.

I am a particle physicist, and this article is confused. The substitution of a glass box _fundamentally_ changes the experiment by allowing phenomena inside the box to correlate with phenomena outside (including your senses). This isn't magic, it's the natural result of light exchanging between stuff inside and out. In the biz, we call this smearing of correlations 'decoherence.'

As for whether the cat 'is' both "dead and alive" in the true black-box Schrodinger scenario, that's very much up for debate. Theorists and philosophers have yet to reach a consensus on how to interpret quantum mechanics, though progress is being made--our quantitative understanding of 'decoherence' being one example.

Don't be fooled: this is an open question.

For more on interpretations: https://en.m.wikipedia.org/wiki/Interpretations_of_quantum_m...

>But if we instead use a glass box, we can then observe the cat along the way.

The use of the word observe is what makes me think this is a troll. Collapsing the waveform through observation is such a common phrasing, it seems silly to assume the author wouldn't have come across it.

We effectively have the whole cat thing going on because the alternative is pilot wave. but that means that a quantum even on the other side of the universe can have repercussions here on earth "instantly", and that was not something physicists were happy to contemplate.

Crazy thing though is that the "holy" double slit experiment can be replicated using water and drops of oil. Set a wave going on the water, and then add drops of oil (particles). What you get out the other end is an interference pattern even though each drop only travel down one slit.

This seems to be just an argument for the Ensemble interpretation of this experiment in opposition to the more commonly held Copenhagen interpretation.

In the Copenhagen interpretation, a system stops being a superposition of states and becomes either one or the other when an observation takes place. Where as the ensemble interpretation states that superpositions are nothing but subensembles of a larger statistical ensemble. Where the state vector would not apply to individual cat experiments, but only to the statistics of many similarly prepared cat experiments.

So it's not that the author is incorrect; they're a proponent of an alternative interpretation.

"I can’t possibly be the first person to notice that Schrödinger’s cat experiment does not change a bit if the box in which the cat resides is made of glass."

Nor are you the first one to have missed the role of the observer in a quantum-mechanical thought experiment: you change the experiment UTTERLY by observing the cat.

There's a very detailed writeup of some similar thoughts in the Fenyman Lectures, focused on the particular case of the electron double-slit experiment and the observational consequences of trying to "see" the electrons passing through one slit vs the other using different wavelengths of photons.

>The words crackpot probably flashed through your mind

In fact that's what makes this post interesting, it's a great example of a crackpot.

Another nice thing about this post is it makes fake news easier to understand. Lots of laypeople could find this plausible.

What in the human brain creates the state of crackpotism? These people are intelligent, usually have some technical understanding, etc. Yet it wouldn't occur to this guy to write up a scientific paper?

A bit unrelated, but there's a possibility that quantum mechanics are not exactly probabilistic and that they're actually deterministic, while still being compatible with observed quantum phenomena. This video explains it well https://www.youtube.com/watch?v=WIyTZDHuarQ

Is there any reason to think the wavefunction "collapses" rather than simply spreading to the observer? Any explanatory power gained? Or is "collapsing" an illusion caused by the basic fact that no version of you gets to see more than one universe?

What a ignorant jackass. The quality of posts here has taken a sharp dive downward.

The observer collapses the wave function of the system. It's like he doesn't understand the original thought experiment, or quantum mechanics at all.

This is what happens when statistics educators teach frequentism.