Schrodinger's Cat

.... "If you place a cat in a box and then place uranium, a geiger counter, and a gun in there, so that when a uranium atom breaks apart in fission, it will register on the geiger counter which in turn is rigged to the gun to shoot the cat."- Schrodinger's Cat phenomenon in quantum mechanics states that "the cat is neither dead nor alive until it is observed." I personally find quantum physics fascinating and incredible, what do you think of the Cat theorem? Stupid or fascinating?

Well, I heard it a little different but besides that I found it to be an interesting thought experiment. My version releases a poison instead of shooting the cat with a gun. That way there is no bullet shooting through the box or any other way to know the state the cat is in until it is observed.

Well, apart from the fact that I disaprove of using a cat...


I do not believe that this theorie is correct.

I've always thought the cat in the box was one of the more clumsy thought experiments. So leaving it behind...

it's just trying to show us that we cannot know the complete state of a particle. And actually, we can prove this correct on the macro level. For instance, let's take your friendly trooper with a radar gun. All his gun is doing is capturing two positions of your car, and the time between those two position readings, and then calculating a velocity. So the gun never knows what your velocity is while it is capturing your positions, and once it has calculated your velocity, it no longer knows where you are. And even if the trooper does know your new position, the velocity no longer is valid, it was calculated off previous positional data.

And the same is true for particles. We can know portions of their total state (position, velocity and spin), but not all of them at the same time.

[edit on 7-9-2005 by Valhall]

Here is my favorite Schrodinger quote:
I wish I had never met that cat!

Because people took the experiment to mean not what he was trying to show. Just that particles could exist in 2 different stages until observed. Anyway, I have never liked the theory.

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Isn't it based on the idea that some states of matter, such as the particular excitement state of a single electron orbital is/can-be affected by a single photon that it becomes impossible to see/observe what that state is without knowing if the photon used to observe caused/changed the state itself or not?

That there is some underlying minimum discrete granularity/particle/energy-packet size to everything in the Universe. In otherwords a single photon [the smallest thing we know of] is too gross a thing to use in observing the finest details of the Universe.

Since a mind, a brain/physics dependent biological system, itself causes more events to happen than it can possibly conceive, that we operate always like bulls in china shops. Unable to perceive/grasph that which is too subtle for us.

Im not sure about the Cat thing though. For the state of the cat to be indeterminate, it would, i believe have to exist [not exist?] outside of time. First of all Cats themselves are observers so the Cat will observe its living existence up to and until it is extinguished. Schrodinger's cat implies that only humans can observe the Universe, which is arrogant to a point of being silly.

But perhaps even requiring a living thing to observe something is a bit of a stretch, since much of the Universe doesn't contain things that we would call living matter. The Earth reportedly existed long before any lifeforms as we recognize them existed, so existence and events do not require living things observing them.

So maybe what one might speculate is that time/existence/an-event depends on some observer aspect/mechanism of the Universe. Maybe the Universe is itself just an observation. Sort of an awareness of a mind on a both grand and intricately complex scale.

We may exist because there is some small awareness of us by the Universe. Eventually as all traces of us as individuals fade into the vagueness of time we eventually cease to exist.

The honor of the Universe being aware of each of us in all its complex vastness is something we probably don't merit, and perhaps should simply revel in as long as it lasts. And in the end our individual self-awareness re-merges with the complex macro awareness of the Universe.

Odd thought: People [life-forms] are awareness[es?] that are separated from the great awareness[es?] in some way. Sort of the peek-a-boo of awareness from itself. The fun [danger?] is the play and interplay of the vast variety of awareness[es].

oops, Starting to rattle.
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So what was the cats name?

Maybe I'm just dumb...


The cat is neither dead nor alive to the protaganist's perspective. In reality it is either dead or alive. I just don't get it. Anyone got anything that will allow my brain to bring forth a suitable paradox? Read a lot on quantam mechanics never have got it tho.

- Nazgarn

Originally posted by nazgarn
Maybe I'm just dumb...


The cat is neither dead nor alive to the protaganist's perspective. In reality it is either dead or alive. I just don't get it. Anyone got anything that will allow my brain to bring forth a suitable paradox? Read a lot on quantam mechanics never have got it tho.

- Nazgarn

LOL - exactly. There are a lot of great scientific paradoxes out there. I never have considered this one of them. To be quite honest - it's just clumsy and stupid.

And really it doesn't say anything about the nature of quantum particles. It says volumes about our inability to measure...that's about it. We can't even measure velocity directly on the macro level - we always lag behind positional data relative to our velocity knowledge. Okay - fine - but that is not unique to quantum mechanics - that's pretty much the way things are period.

To the question about the cat being an observer: once again this was just an example that Schrodinger had made up when he first made his theory. I have heard the theory of the photon light and how that might change the character of the object being observed but no one knows for sure. What is strange is that this really isnt a theory, it has been proven in a laboratory. Along with this theory comes along the hint of a "cosmic consciousness" or "dieties." But for now this thread will stay on the one topic of Schrodinger's cat.

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The cat proposition implies that the events inside the box are outside the time sequence of events.
ie. While the rest of the world goes on in a sequential manner, inside the box time is suspended.

Im not quite sure if all the intervening intervals of time suddenly happen all-at-once [are condensed] or not in the proposition, or if time is simply suspended/stopped until the box is opened when it re-starts up.

This may even be the case for sub-atomic particles and forces existing in an indeterminate state outside of time, but in the macro Universe,
Only at a lightspeed differential does [relative] time become completely suspended in the macro Universe of our existence and experience.

For a box that is relatively stationary in a lab, in the macro Universe [scale], time progresses in parallel [unison?].

The proposition also implies a divergent/branched/fuzzy source of events that converge as the box is opened.

Like the ball of the roulette wheel just keeps spinning indefinately until stopped with observation. Although i think it is actually more like the ball is in all slots at once with proportional probability. It sort of clicks like a lightswitch to a single outcome. Prior to opening it exists as a probability field/function.

Also makes one wonder if there would be some way of manipulating the outcome of opening the box.

I wonder if there is some method of changing/manipulating the probabilities inside the box, guaranteeing a desired outcome?

Within the Universe time is relatively suspendable upto stopping time at light speed. If you could get to the point of reversing time, you could run time back and forth for the lab until you got the desired outcome.

But you might only be able to do this for sub-micro particles/events.
The improbabilities of affecting a macro event of the Universe are so great that it would approach an infinite amount of manipulations to get some desired/altered outcome.
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This isnt a paradox, this is like saying if a tree falls and no one is around to hear it did it make a sound? yes, you just didnt hear it. Same thing with this, Unless his point is you cant be sure of anything until you do observe it this 'experiment' makes no sense.

Originally posted by slank
Isn't it based on the idea that some states of matter, such as the particular excitement state of a single electron orbital is/can-be affected by a single photon that it becomes impossible to see/observe what that state is without knowing if the photon used to observe caused/changed the state itself or not?

That there is some underlying minimum discrete granularity/particle/energy-packet size to everything in the Universe. In otherwords a single photon [the smallest thing we know of] is too gross a thing to use in observing the finest details of the Universe.

Slank,
Unfortunately for our sanity, this is not the case. If you research the "two-slit" experiment you will learn something that is completely absurd and unacceptable, not to mention unbelievable, but nonetheless apparently true. The act of observing actually changes the reality of the situation. And this is absolutely not due to some interference from the method of observation, as you surmise about photons in your post.

Originally posted by slankIm not sure about the Cat thing though. For the state of the cat to be indeterminate, it would, i believe have to exist [not exist?] outside of time. First of all Cats themselves are observers so the Cat will observe its living existence up to and until it is extinguished. Schrodinger's cat implies that only humans can observe the Universe, which is arrogant to a point of being silly.

Here you have cut the Gordian Knot. This is the clearest refutation of this paradox I've seen (though this is not the first time I've seen it). Of course the cat is an observer, presumably he knows if he's alive.

Harte

Many parts of Quantum physics cannot be reasoned with, often times in this forum individuals try to reason with the ideals of the theories. Even the top physicists of the world cannot apply explanations to these puzzling ideas. I have heard of the photon explanation before but it doesnt work, i haven't heard of the Cat's consciousness before- ill try to find out. Also about the twin-slit experiment, doesn't light travel in waves? so when it goes through the slit, because its travels in waves- it doesnt just go straight through but it creates an inference pattern on the back screen. I just think that when the theory is put in that light (lol) it becomes clearer to ones perception.

All it says is that we can't know something has happened even if we think it might if we can't get the information. A scientific way of saying "You see a squashed rat on the street. It was run over by a car. "Says who?" As Val said, nothing huge or important, just "cool."

Originally posted by horten229v3
...Also about the twin-slit experiment, doesn't light travel in waves? so when it goes through the slit, because its travels in waves- it doesnt just go straight through but it creates an inference pattern on the back screen. I just think that when the theory is put in that light (lol) it becomes clearer to ones perception.

Horten,
The bottom line with the two slit experiment is that light behaves as a particle when going through one slit, as a wave when going through two slits and as a particle again when going through two slits if you try to find out which slit each photon went through.

This is true not only of photons, but also of electrons, and any other particles, including some atoms, as I recall. Even if the particles are fired one at a time at the slits, even if you wait for a minute or so between firing particles, you will still get a wave interference pattern on the back screen, or a "buckshot" pattern if you try to determine which slit each particle went through.

Harte

I always thought this was meant to show that object and observer were somehow linked. That the observered was somehow affected by the observered.

I always thought this was meant to show that object and observer were somehow linked. That the observered was somehow affected by the observerer.

[edit on 29-7-2005 by halfhand]

If a tree falls in the woods and nobody is there to hear it, does it make a sound?

How is this cat thing different?
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The Rules of Quantum Particles sometimes appear to defy what we "know" about the universe.

Quantum mechanics claims that our observation of a sub-atomic particle effects that particle. This has been explained by Harte.

Schrodinger was one of the fathers of Quantum mechanics but he, like Einstein, didn't like the things it was saying. He came up with his Schrodinger's Cat Paradox to try and show what is wrong with Quantum mechanics. You can't preform the "experiment" because it was meant as a mind puzzle. So the cat observing it's own state is irrelavant to what he was saying. What he was saying was basically this. According to the laws of Quantum mechanics the cat is both alive and dead at the same time until we check on it. This, Schrodinger said, was obviously impossible, and showed a fundamental flaw with quantum mechanics. That's why he came up with the paradox.

Then we fastforward a little, I don't remember if it was the 60s or 70s but some young physicists find the "answer" to the puzzle. They said that in every instant there is and infinate number of alternate universes being spawned be every single possible quantum state of the universe. So the cat was both alive and dead(and not in the box, and in the process of dying) at the same time but at the moment we check one of those states becomes our "reality". It's a little more complicated than that, but basic thats it.

It's that interpretation that revived interest in the Schrodinger's Cat Paradox in more recent times and it shows up quite a lot in sci-fi.

I'm not saying I personally believe that interpretation but I believe nothing is true and all is possible so what do I know.