
What did Schrodinger's Cat experiment prove? (2013) - slynn12
https://wtamu.edu/~cbaird/sq/2013/07/30/what-did-schrodingers-cat-experiment-prove/
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lmm
Nonsense. Under the Copenhagen interpretation (which I do not personally
subscribe to, but it is a legitimate interpretation and it has its defenders),
when one particle interacts with another particle that's in a superposition,
the result is that both particles are in an entangled superposition. Cat,
Geiger counter and gunpowder can thus all be in an entangled superposition;
one can argue that this is absurd, but Einstein also thought that the EPR
experiment showed that quantum mechanics was absurd, and actually that result
has been experimentally verified.

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phkahler
I prefer to replace Schrodinger's cat with Schrodinger's brother. Now you
claim to have a human observer in a superposition of dead and alive states. He
will not suddenly experience collapse when let out of the box to greet
Schrodinger. The entire notion of "wave function collapse" is a fictional
construct that can not be observed because it doesnt happen.

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karlicoss
Schrödinger's brother is Wigner's friend

[https://en.m.wikipedia.org/wiki/Wigner%27s_friend](https://en.m.wikipedia.org/wiki/Wigner%27s_friend)

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at_a_remove
I never thought of it as something to, uh, _prove_ but more like yet another
way to point out the limits of our understanding when it comes to our ability
to measure something.

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_alex_
This exactly. The simplest explanation for quantum behavior is just that we’re
unable to measure it. There are a lot of weird and magical explanations that
people have come up with in order to write formulas that work.

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badrabbit
I believe experiments were conducted in a way measurement capacity is
irrelevant. Either it's an effect of things being rendered (as in a real
"simulation",much like pixels in a game depened on the "camera" to render) or
there is an undiscovered quantum property that is confined to dimensions known
or unknown that have yet to be discovered.

In QM you have the observer, in relativity you have the reference frame, I
think physics is exploring fundamental properies of the reality we
experience,that it is a subset of something else.

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_alex_
People talk about a quantum particles as being in many places at once. When
you ask what that means, the explanation is that they aren’t in one place,
their position is represented as a probability curve of the places that they
might be right now, and then when an observer observes the particle, that
curve flattens down to where the particle is.

That seems like a very anthropocentric view of the universe. Why would it
matter whether a particle is “being observed”, UNLESS the act of observation
has a side-effect. If “observation” is purely passive then it can’t affect
anything, by definition.

A MUCH simpler explanation is that the way that we observe things (by looking
at them) is by bouncing photos off of them. Quantum particles are small enough
that bouncing a photon off of it can change its course.

Here’s an analogy : you’re blind, but you’re super good at throwing and
catching basketballs. The way that you observe the world is by throwing a
basketball and then timing how long it takes to come back to you and catch it,
and by observing if it comes back at an angle or with some spin on it. Imagine
you come across a pigeon. You throw the basketball at the pigeon. You observe
strange behavior of the pigeon when you “observe” it vs when you don’t. You
formulate the pigeon uncertainty principle. You describe pigeons as spooky.
You just accept that pigeons follow different physics than school buses.

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badrabbit
I believe the experiments were conductes in vaccum without light or photons.
The double silt experiment I believe. From what I gather,they send particles
in a controlled environment and see where they land AFTER it went through the
silts, so interactions after the silt shouldn't affect which silt it goes
through. That's why I said it could be some unknown interaction between the
observer and the particles. Or unknown propery of a known interaction like
gravitation.

To me, it sort of sounds like how time dilation works in relativity except for
a different dimension.

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juped
I think of it as driven by thermodynamics - the state is "collapsed" when it's
too informationally entangled with the rest of the universe. It's not really
"collapse", just our good friend positive entropy.

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pa7x1
This is indeed the case, this process is called decoherence.
[https://en.wikipedia.org/wiki/Quantum_decoherence](https://en.wikipedia.org/wiki/Quantum_decoherence)

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chadcmulligan
So does that mean the idea of a "multiverse" is in the same box?

Edit: I'll rephrase (I'm serious) - isn't the idea of the multiverse based on
the schrodinger's cat in a box idea, and the need for an observer? Or is the
whole multiverse idea just sci fi? Or is there another physical basis for the
idea of a multiverse?

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bawolff
The paralell universe thingy or the "multiple worlds" interpretation (which is
what i assume you mean) is one of the competing philosophical explanations for
what is going on during quantum mechanics. Like most topics in metaphysics,
there is no evidence either way, and there are competiting interpretations
that are just as good (but don't capture the imagination in the same way). Its
based off the cat experiment in that its trying to explain what is happening
there metaphysically, but the parallel universe interpretation doesn't make
any testable predictions beyond those made by quantum mechanics, so neither
the experiment nor any other experiment, proves it.

Any sort of visiting paralell universes stuff is pure sf.

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chadcmulligan
yes, thanks, thats what I meant. While I'm here, something I've always
wondered about the multiple worlds interpretation is where does the energy
come from for all these parallel universes? Like if each possible event causes
a split then haven't we just doubled the energy we started with? since we've
created a whole new universe.

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hartator
Yes, and there is billon of quantum events happening right now in each cubic
inches of air around you. So billions of universe literally from thin air.
Multiverse is fun but absurd.

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pa7x1
You seem to argue from an economic point of view, as if it was too "expensive"
or "wasteful" to have all those universes. But MWI doesn't add any postulates
to QM, in fact it is the simplest of the interpretations and a direct
translation of what the math of QM says. All those universes are as
"expensive" as the quantum mechanical state superposition they represent, and
the superposition is a central tenet of QM and thoroughly tested. Your
conclusion could be rephrased as "quantum superposition is fun but absurd".

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imvetri
There is something and there is nothing. We think we are something, but in
someone else's view we are nothing.

You are the cat inside the box. You exist as a person, live in a planet and
the entire setup could and couldn't be real. The experiment prooves that
something is uncertain and all these are nonsense.

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NewEntryHN
> as soon as the radioactive atom interacts with the Geiger counter

Doesn't the paradox arise precisely because the time at which the atom will
interact is probabilistic?

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Taniwha
Pretty sure no one's ever actually done this experiment, have you ever tried
to put a cat in a box?

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huffmsa
They love boxes. Or taped rectangles.

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woliveirajr
It proved that it was and wasn't an experiment at the same time, and that the
experiment's setup was and wasn't detailed enough and you could only know it
when you read the teaching material.

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cd1980
I have been mislead about Schroedinger's cat, but now I get the absurdity.
However, I also feel there might be a conceptual mistake in the experiment
setup: there -is- a conscious observer present inside of the sealed box: the
cat. Thus there is no super-position and therefore the cat will observe itself
when it dies (or stays alive), matching later experiments' results. Science:
it works! But Schrodinger's attempt at absurd comedy seems to have failed.

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bawolff
> there -is- a conscious observer present inside of the sealed box: the cat.
> Thus there is no super-position and therefore the cat will observe itself

I think you are misinterpreting what "observe" means in this context.
Conciousness has nothing to do with it.

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mongol
The article mentions "conscious observer" six times. Surely it must mean
something involving consciousness?

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ShamelessC
This usage is misleading and surprisingly common because it helps to frame the
problem well. To be clear, an "observer" in the quantum context is merely
anything which is measuring the outcome of an event. It need not be conscious
but it can be.

Having said that, I think you're actually correct to point this out! The cat
will obviously have a look around inside the box and likely cause wavefunction
collapse. I believe the cat is meant to be fundamentally unable to effect
things though.

After all, it's mostly an interesting problem because it posits that anything
that could be "alive" inside the box would be in a superposition of alive and
dead which is something that's never been observed and probably can't happen
due to the unstable nature of wavefunction collapse in the real world.

