Cat In The Box - Thought Experiments

[Cheerful Charlie]

It is claimed that if you put a cat in a box with a random device that can release poisonous gas, the cat is neither alive or dead until the box is opened. At that point then the cat is either dead or alive.
Schroedinger's unfortunate cat.

You have a box with an air tight lid. You place the cat in the box and close the lid. You know there is enough air for the cat to live about a half hour. You know thus that after an hour, you have a very dead cat.

So when does the cat's ware function collapse, resulting in a dead cat? When you designed the experiment? When you shut the box's lid? In half hour? In an hour? When you open the box knowing full well the cat will be dead? When we observe a very dead cat?

Suppose you have a timer which will release poisonous gas in 15 minutes. Does that knowledge it will happen collapse the wave function? Or does the cat have to actually die?

Suppose you perform this experiment but at 10 minutes you roll a die. If the die is even, you let the cat die. If odd, you save the cat. Does rolling the die collapse the wave function?

Supposing you climb in a box and this box is shut. You are neither dead or alive. If the box is placed in a deep mineshaft and exists for centuries unmolester, have you in a sense lived centuries or not?

How many dead/undead cats can dance on the head of a pin?

Show all your work. There will be a test.

 

[Cheerful Charlie]

"This is the stupidest thread ever!" is not an answer.

 

[Bomb#20]

Please. Please. Just for a minute. Just for half a minute! Please let me put the cat in the box!

- Ursula K. LeGuin's dog​

 

[ryan]

Once you have been physically affected by the result of the cat living or dying, the wave function collapses. For example, if the thud of the cat hitting the floor causes a small vibration that you consciously or unconsciously detect.

Another interesting thing is that your knowledge of the cat dying is in a state of uncertainty relative to another observer that you have no yet physically affected since acquiring the new knowledge. At least that's one of the more common interpretations of quantum mechanics, namely the many worlds interpretation.

 

[DBT]

Everything exists in all possible states (probability wave function) until an act of observation collapses probability into a definite state, aka, Copenhagen interpretation....or the cat is in all possible states but only one state is realized in each division/world state, aka. many worlds interpretation....

 

[Valjean]

I agree with DBT.

Advancement in Science frequently begins with thought experiments. Special Relativity began with Einstein imagining himself riding on a light wave.

 

[bigfield]

It is claimed that if you put a cat in a box with a random device that can release poisonous gas, the cat is neither alive or dead until the box is opened. At that point then the cat is either dead or alive.
Schroedinger's unfortunate cat.

You have a box with an air tight lid. You place the cat in the box and close the lid. You know there is enough air for the cat to live about a half hour. You know thus that after an hour, you have a very dead cat.

So when does the cat's ware function collapse, resulting in a dead cat? When you designed the experiment? When you shut the box's lid? In half hour? In an hour? When you open the box knowing full well the cat will be dead? When we observe a very dead cat?

Before the half hour is up, the cat's state could be dead or alive, so there is still uncertainly about it's state. After the half hour has elapsed, there is no longer any uncertainty about the cat's state; it is certain to be dead and therefore there is no longer a quantum superposition of a dead cat and an alive cat.

Suppose you have a timer which will release poisonous gas in 15 minutes. Does that knowledge it will happen collapse the wave function? Or does the cat have to actually die?

If the cat is certain to be alive before the fifteen-minute mark and certainly dead afterward, then there is never a quantum superposition that can be collapsed.

Suppose you perform this experiment but at 10 minutes you roll a die. If the die is even, you let the cat die. If odd, you save the cat. Does rolling the die collapse the wave function?

At no point is there any uncertainly about the cat's state. The cat is certainly alive before the die is rolled, and certainly dead or certainly alive once the die is cast

Supposing you climb in a box and this box is shut. You are neither dead or alive. If the box is placed in a deep mineshaft and exists for centuries unmolester, have you in a sense lived centuries or not?

From your own point of view, you are certain that you are dead or alive (although you can't 'know' that you are dead). From an outside observer's point of view, your state is unknown, but this thought experiment is complicated by the fact that one can be certain that you are dead long before several centuries have elapsed.

 

[ryan]

At no point is there any uncertainly about the cat's state. The cat is certainly alive before the die is rolled, and certainly dead or certainly alive once the die is cast

If nothing collapses the wave function (no decoherence) in the box, then why would the cat be in a single state?

And if the wave function collapse is not correct, then the other most common interpretation is that the observation is made in split universes with either outcome, the many worlds interpretation.

Read, "In particular, whenever a measurement is performed by an observer, the observer's minds develop mental states that correspond to perceptions of the different outcomes, i.e. corresponding to the worlds A or B in our example.".

from http://plato.stanford.edu/entries/qm-manyworlds/#1

This means that the cat is alive in one universe and dead in another; for all practical purposes it's alive and dead until you open the box.

 

[Bomb#20]

You have a box with an air tight lid. You place the cat in the box and close the lid. You know there is enough air for the cat to live about a half hour. You know thus that after an hour, you have a very dead cat.

So when does the cat's ware function collapse, resulting in a dead cat? When you designed the experiment? When you shut the box's lid? In half hour? In an hour? When you open the box knowing full well the cat will be dead? When we observe a very dead cat?

Assuming it's a proper SC box with a Geiger counter and poison and all, presumably when you open the box the wave function collapses from a superimposed state of a dead poisoned cat and a dead suffocated cat, observationally distinguishable by autopsy.

 

[Malintent]

The dead / alive proposition of the cat is an unfortunate artifact of some very interesting, if not useful, math.

The cat is alive, until it is not. What you think or perceive of the cat does not matter.

you cannot think or perceive the cat to death.

Talking about that cat in the box is no different than a time traveler talking about killing Hittler's grandfather.

 

[Kharakov]

The dead / alive proposition of the cat is an unfortunate artifact of some very interesting, if not useful, math.

Being able to not describe something exactly with extreme precision is...

What did you come up with? A way to not say where something is with extreme precision. It's the most highly accurate means of not describing where something is in the history of existence.

 

[Cheerful Charlie]

The dead / alive proposition of the cat is an unfortunate artifact of some very interesting, if not useful, math.

The cat is alive, until it is not. What you think or perceive of the cat does not matter.

you cannot think or perceive the cat to death.

Talking about that cat in the box is no different than a time traveler talking about killing Hittler's grandfather.

Yes, Schroedinger meant his cat as an reductio ad absurdum, demonstrating the silliness of the idea one had to observe the cat to collapse its wave function to decide if the cat is dead or alive. Indeed, the cat is alive until it dies, if it dies. What needs clarification on those who believe in a cat neither dead nor live in the box is clarification of what they mean by observe.

If there is a camera in the box, and a light, why does this not count as an observation, even if nobody observes the cat in a monitor? Suppose somebody observes the cat in the monitor but does not realize what they are viewing, does that suffice? Or does it take somebody who knows what the experiment is about to collapse the wave function?

 

[Malintent]

I think it is a lot more simple than that (although I accept this is more a criticism of my understanding than of the nature of scientific understanding, of course)...

To observe something requires that something to have a stimulus effect on our senses, or our tool's sensors. The smallest degree of sensory responses can only be triggered by realatively macro things.. sound needs relatively HUGE air molecules moving around... sight needs photons.. touch needs some degree of pressure.. smell needs relative huge molecules.... etc...

So, when we want to observe the very very very very small, we need to cause that which we wish to observe to generate sufficiently large reponses that our tools can measure. It is my belief that it is our tools that are causing these odd effects, and not that (passive) observations are simply revealing these effects.

Does that make any sense? I am saying that our measurement tools are creating effects, not measuring existing effects.

"looking" at the cat does not kill it. Zapping it with microwave energy so that we can get a reading on certain energy states of its particles is killing the damn thing.. so to speak.

 

[Kharakov]

You forget cancelation of wavy gravy 2 slit experiments (whenever you use only one mind).

 

[Cheerful Charlie]

And now for something completely different.

If a theorist believes a cat in a box has an uncollapsed wave function, and that it needs an intelligent observer to collapse the wave function, what sort of experimental box with cat could be set up to prove that claim is true?

Consider this possibility, a box with cat and camera. The proceedings are recorded. If one opens the box and finds a dead cat, then views the .mpg, is that .mpg a record of what happened or does that record remain in an uncollapsed wave function until viewed, and why would it be in perfect agreement with the observation that the cat is dead?

 

[bilby]

"In fact, the mere act of opening the box will determine the state of the cat, although in this case there were three determinate states the cat could be in: these being Alive, Dead, and Bloody Furious." - Terry Pratchett.

 

[DBT]

And now for something completely different.

If a theorist believes a cat in a box has an uncollapsed wave function, and that it needs an intelligent observer to collapse the wave function, what sort of experimental box with cat could be set up to prove that claim is true?

Consider this possibility, a box with cat and camera. The proceedings are recorded. If one opens the box and finds a dead cat, then views the .mpg, is that .mpg a record of what happened or does that record remain in an uncollapsed wave function until viewed, and why would it be in perfect agreement with the observation that the cat is dead?

Presumably the wave/particles of the brain of the observer are entangled with the object being observed, so whatever a camera happens to 'observe' is less important than what the brain represents in the form of conscious observation when it perceives the results.

 

[Cheerful Charlie]

And now for something completely different.

If a theorist believes a cat in a box has an uncollapsed wave function, and that it needs an intelligent observer to collapse the wave function, what sort of experimental box with cat could be set up to prove that claim is true?

Consider this possibility, a box with cat and camera. The proceedings are recorded. If one opens the box and finds a dead cat, then views the .mpg, is that .mpg a record of what happened or does that record remain in an uncollapsed wave function until viewed, and why would it be in perfect agreement with the observation that the cat is dead?

Presumably the wave/particles of the brain of the observer are entangled with the object being observed, so whatever a camera happens to 'observe' is less important than what the brain represents in the form of conscious observation when it perceives the results.

If I am observing the cat via cat cam 1000 miles away via the internet, how is the wave function transmitted? And transmitted back if I have no 2 way communication with the cat cam?

 

[DBT]

Presumably the wave/particles of the brain of the observer are entangled with the object being observed, so whatever a camera happens to 'observe' is less important than what the brain represents in the form of conscious observation when it perceives the results.

If I am observing the cat via cat cam 1000 miles away via the internet, how is the wave function transmitted? And transmitted back if I have no 2 way communication with the cat cam?

I don't think distance makes much difference to entangled particles. Einstein's lament about 'spooky action at a distance', etc. What the observer sees, either as the object/collapsed wave/particle position (Copenhagen) or its expression in this universe rather than other universes (string theory/many worlds) being determined by an entangled interaction between input states and mental representation of the perceived states. The processor/observer, a brain, not being separate from the world at large or the thing being perceived.

In other words, there probably is no such thing as a detached, isolated or independent observer.

 

[Malintent]

Presumably the wave/particles of the brain of the observer are entangled with the object being observed, so whatever a camera happens to 'observe' is less important than what the brain represents in the form of conscious observation when it perceives the results.

If I am observing the cat via cat cam 1000 miles away via the internet, how is the wave function transmitted? And transmitted back if I have no 2 way communication with the cat cam?

"spooky action at distance"... aka Bell's Theorem