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Cleedow
11-16-2011, 01:37 PM
Seriously, is there anyone who can explain this paradox? I've been trying to get it for ages but no matter where or how i get it explained i still don't understand what's up with this cat :P I don't see the paradox..

stillmatic07
11-16-2011, 01:39 PM
There is no spoon.

HammerLegionary
11-16-2011, 01:42 PM
Profact: It was used to justify killing poor innocent kittys.
Source, some purple eyed gguy.

IcarusNine
11-16-2011, 01:45 PM
The cat's fate is tied to a quantum particle.
The paradox is that the quantum particle's state is unknown until it can be observed (which sounds plausible in the mystical world of quantum physics), and thus the cat's state is unknown until it can be observed (which sounds implausible in the macroscopic world of Cats Don't Work That Way).

joeylawn
11-16-2011, 01:47 PM
The problem with the Schrodinger's Cat thought experiment is that cats don't obey the laws of quantum mechanics - they only obey Cat Laws! :D

frogsmoothy
11-16-2011, 01:49 PM
The cat's fate is tied to a quantum particle.
The paradox is that the quantum particle's state is unknown until it can be observed (which sounds plausible in the mystical world of quantum physics), and thus the cat's state is unknown until it can be observed (which sounds implausible in the macroscopic world of Cats Don't Work That Way).

This is pretty much it. The idea that you can't determine the cat's state until observed is ludicrous because, well, cats can't be both alive and dead.

Cleedow
11-16-2011, 01:54 PM
This is pretty much it. The idea that you can't determine the cat's state until observed is ludicrous because, well, cats can't be both alive and dead.

Exactly. So why would they make such a big deal out of it? SCIENCE :D

joeylawn
11-16-2011, 01:59 PM
It has to do with Heisenberg's Uncertainty Principle - you cannot know both the position and momentum of a subatomic particle at the same time - only probabilities.

http://en.wikipedia.org/wiki/Heisenberg_uncertainty_principle

Achillies
11-16-2011, 02:00 PM
The cat is both alive and dead until you open the box and find its carcass laying there, lifelessly.

stillmatic07
11-16-2011, 02:05 PM
The cat is both alive and dead until you open the box and find its carcass laying there, lifelessly.

...playing a banjo to his favorite song while another cat jumps out from behind and...

Snorkel
11-16-2011, 02:13 PM
I understood that Shroedinger came up with this to demonstrate the problems with some principle.

*looks it up*

It illustrates what he saw as the problem of the Copenhagen interpretation of quantum mechanics applied to everyday objects.
http://en.wikipedia.org/wiki/Schrodinger%27s_cat

That's probably it.

joeylawn
11-16-2011, 02:13 PM
....saves you from the zombie about to bite your neck....

IcarusNine
11-16-2011, 02:17 PM
Exactly. So why would they make such a big deal out of it? SCIENCE :D

Paradoxes are the blue screen of death for mathematical theories.

frogsmoothy
11-16-2011, 02:33 PM
It has to do with Heisenberg's Uncertainty Principle - you cannot know both the position and momentum of a subatomic particle at the same time - only probabilities.

http://en.wikipedia.org/wiki/Heisenberg_uncertainty_principle

no one said anything about the heisenburg uncertainty principle. I'm pretty sure we know how fast the cat is moving.

joeylawn
11-16-2011, 03:02 PM
no one said anything about the heisenburg uncertainty principle. I'm pretty sure we know how fast the cat is moving.

well maybe I'm wrong, but I thought what killed or not killed the cat in Schrodinger's thought experiment was a decaying radioactive particle setting off a gieger counter, which breaks a jar of hydrogen cyanide*.

Radioactive decay cannot be predicted on a small scale, that's why the half-life measurement** is used.

*noticed how I used Hydrogen Cyanide instead of "Cyanide". There is no such molecule called "cyanide". Cyanide is an radical ion CN-.

**The sequel to Half-Life 2's release apparently can be measured with the decay of Uranium-238. :rolleyes:

IcarusNine
11-16-2011, 03:08 PM
Except that this has to do with quantum superposition, not uncertainty.

joeylawn
11-16-2011, 03:16 PM
Except that this has to do with quantum superposition, not uncertainty.

oh ok, I thought they were the same.

This also helps me understand how Quantum Computing is possible, as it also relates to superposition, not uncertainty.

Quantum Computing would be impossible if uncertainty were involved, as I formerly thought.

charlysotelo2
11-16-2011, 03:18 PM
I dont think anyone but Achilles has given the right answer. The cat is BOTH alive AND dead, until we open the box.

EDIT:

here is a simple video that explains it:

http://www.youtube.com/watch?v=CrxqTtiWxs4

frogsmoothy
11-16-2011, 03:32 PM
I dont think anyone but Achilles has given the right answer. The cat is BOTH alive AND dead, until we open the box.

EDIT:

here is a simple video that explains it:

http://www.youtube.com/watch?v=CrxqTtiWxs4

But that's not actually the case, because that would be stupid. Cats do not behave the same way individual quantum particles do. The whole scenario was designed to make quantum mechanics look stupid, in my opinion it accomplishes this.

monkeedude1212
11-16-2011, 03:55 PM
But that's not actually the case, because that would be stupid. Cats do not behave the same way individual quantum particles do. The whole scenario was designed to make quantum mechanics look stupid, in my opinion it accomplishes this.

The Cat is not altering it's behavior though. It's just breathing, it's life or death is dependant on the individual particles surrounding the box acting a certain way. Whether the poison makes it into the box or whether the poison does not make it into the box is based on the particle's uncertainty. The permeable rate of 50% is what gives it the 50% chance of living or not living, and is related the to the superposition of each individual particle having a 50% chance of entering or not.

Since we can see that quantum particles act differently when observed* (http://www.youtube.com/watch?v=DfPeprQ7oGc)than when they do unobserved, they are suggesting that the cat has two probable outcomes and it will only be one or the other once you observe it, but until it's observed, it is actually containing both possibilities, which can interfere with one another, which means the Cat IS BOTH alive and dead.

The immediate sensible thing is that we don't understand how our observations are collapsing the wave function of quantum particles, but there must be something to it if this field has enough research going on.

*This video is meant for kids, but that just makes it simple and a bit funny to watch.

AlecJ32
11-16-2011, 03:57 PM
The cat's fate is tied to a quantum particle.
The paradox is that the quantum particle's state is unknown until it can be observed (which sounds plausible in the mystical world of quantum physics), and thus the cat's state is unknown until it can be observed (which sounds implausible in the macroscopic world of Cats Don't Work That Way).

Right. Schrödinger devised this little idea as a way to illustrate how he disagreed with Copenhagen interpretation.

BurtonJ
11-16-2011, 04:02 PM
they only obey Cat Laws! :D

And who enforces those laws? These guys! (http://www.youtube.com/watch?v=K_AdxJWFUh4)

HellJumper
11-16-2011, 04:15 PM
Schrodinger's Cat:

Wanted dead and alive.

Smertnik
11-16-2011, 04:20 PM
I wouldn't know, I'm more of a dog person.

frogsmoothy
11-16-2011, 04:26 PM
Schrodinger's Cat:

Wanted dead and alive.

TAKE SO MUCH OF MY REP

Axe on
11-16-2011, 04:36 PM
This video explains it. (http://www.youtube.com/watch?v=IOYyCHGWJq4)

Larry1212
11-16-2011, 04:43 PM
And who enforces those laws? These guys! (http://www.youtube.com/watch?v=K_AdxJWFUh4)

I can't believe I used to watch that crap...

chaoticpix93
11-16-2011, 04:44 PM
according to the theory though the cat is simultaneously alive and dead because we aren't observing the cat in whatever state the atom is that we are observing in the box. It's not until we open the box do we know if the cat is alive and dead.

it's not a closed system either, say we had this done in a closed room, and so we are no in a superposition of states until they open the door to observe weither we can report the cat is alive and dead.

The thing is, it's a thought experiment. It's not really validated by reality but used to explain how quantum reality just doesn't behave like classical physics.

It doesn't matter what killed/not killed the cat because the point is the observation of the atom causes us to be in one of two states. The same can be said for any set of observations in the quantum universe. If you observe it, you immediately disturb it. If you observe the electron as a wave, you then can't see it as a particle. If you view it as a particle it's no longer got wave properties. Google the double-slit experiment for more information.

Snorkel
11-16-2011, 04:45 PM
I saw a cartoon in the I Hate Cats Book which I think had Schroedinger experimenting whether cats obey the laws of fluid dynamics...by firing them out of a cannon at a brick wall...

...wish I could find it.

TZK203
11-16-2011, 04:47 PM
I saw a cartoon in the I Hate Cats Book which I think had Schroedinger experimenting whether cats obey the laws of fluid dynamics...by firing them out of a cannon at a brick wall...

...wish I could find it.

It's all in your head. ;)

CTRL ALT DEL !
11-16-2011, 04:52 PM
What if they opened the box and it was a puppy?

TZK203
11-16-2011, 04:54 PM
What if they opened the box and it was a puppy?

I shout in astonishment. (http://www.youtube.com/watch?v=tzJ_c_9wDzg&feature=related#t=0m12s)

Rocktail
11-16-2011, 04:56 PM
Cats, how the crap do they work?

Gustave5436
11-16-2011, 06:07 PM
Seriously, is there anyone who can explain this paradox? I've been trying to get it for ages but no matter where or how i get it explained i still don't understand what's up with this cat :P I don't see the paradox..

It's not a paradox, it's a "haha look at how stupid those Copenhagen interpretation guys are. The absurdity of it! A cat, both alive and dead at the same time; what nonsense." It's closer to Swift's modest proposal, really.

Schrodinger himself was a fan of local hidden variables iirc (a wholly deterministic interpretation that doesn't have wavefunction collapse at all), although that has since been proven false.

stillmatic07
11-16-2011, 06:10 PM
What if in the box, when opened, there were three cats: Two dead, one giving birth to a frog.

joeylawn
11-16-2011, 09:21 PM
Then there is the superposition of states of the jar of hydrogen cyanide - you can't see inside, so you don't know if the jar is broken or not - so it's both Broken and Non-Broken! :D

Gamebreaker
11-17-2011, 01:57 AM
As a religious person, every time someone uses plain logic to deny the concept of God. Then Schroedingers cat reminds me that he might as well deny the reality he is existing in.

helidan
11-17-2011, 02:04 AM
The Double-Slit experiment is the one that gets me really interested.

Designed to illustrate particle/wave duality, it never fails to demonstrate that the mere act of observing an event collapses the wave function.

There are indeed wierd things going on down in the quantum world:confused:

Odra
11-17-2011, 02:22 AM
I prefer Cracked's analysis (http://www.cracked.com/article_19419_6-parodies-that-succeeded-because-nobody-got-joke.html) of it.

Menice22
11-17-2011, 03:45 AM
I still have nightmares about that cat...

ALSO: http://xkcd.com/45/

Dr.Boo.j2
11-17-2011, 04:42 AM
A quantum particle can have two states simultaneously. Lets say it's state A and state B. If the quantum particle is state A, it causes the cat to die, if it's state B, it causes the cat to stay alive.

But since the particle has two states at a time, the cat would be both dead and alive at the same time.

Now that we're talking about these things that you just cant grasp no matter how many explanations you get: I always wondered how wormholes work. Theoretically, wormholes connect one point in space-time with another distant one through a shortcut. Space-time can sometimes somehow fold bringing two points close to each other and link those with a wormhole.
Imagine it if you'd compare space-time with a sheet of paper and connect one side of the sheet with the other by folding the paper.

Ok I understand the theory, but a sheet of paper is two-dimensional while space-time is 4 dimensional. I just cant grasp how you can represent space-time as something flat.

Antikythera
11-17-2011, 05:18 AM
The Schrödinger's cat experiment was to proof that the Copenhagen interpretation would never work, it was to illustrate the problem of it.

http://simple.wikipedia.org/wiki/Schr%C3%B6dinger%27s_cat
http://simple.wikipedia.org/wiki/Copenhagen_interpretation

Read these two articles, and I'm sure you'll get it after that, if not just put some thought into it.

Psychrophile
11-17-2011, 08:25 AM
As a religious person, every time someone uses plain logic to deny the concept of God. Then Schroedingers cat reminds me that he might as well deny the reality he is existing in.So might you by assuming God exists. It works both ways. :confused:

skiddlywibble
11-17-2011, 08:34 AM
The whole scenario was designed to make quantum mechanics look stupid, in my opinion it accomplishes this.

Exactly. Only people then started using it as a easy way to explain quantum physics in layman's terms. :rolleyes:

marie pavie
11-17-2011, 09:13 AM
I don't care what happens to Schrödinger's cat. Call me cold hearted, but I'd put Schrödinger in that box too, & rocket it into the sun. It reminds me too much of a table of guys at half an hour till last call.



"How do ya like them apples"

joeylawn
11-17-2011, 09:40 AM
The real question asked by the Schrödinger's Cat Thought Experiment is:

WHO WAS PHONE?

Dmytry
11-17-2011, 10:22 AM
Seriously, is there anyone who can explain this paradox? I've been trying to get it for ages but no matter where or how i get it explained i still don't understand what's up with this cat :P I don't see the paradox..
Well this was not a paradox originally, but a good argument against the role of observer which turns coexisting alive cat and dead cat into definitely alive cat or definitely dead cat by 'observing'. It would get even weirder where the cat would be fed instead of killed - this would turn a hungry cat and full cat into either hungry cat, or full cat, making one of the cats vanish. Also, it was told between two physicists who agreed that cats are observers too.

Most good physicists agree that either something special happens to objects much larger than a few atoms, and the cat is definitely dead or definitely alive in the experiment, OR the entire universe splits into two universes, one with alive cat, and other with dead cat (and when box is opened, the two observers that see alive cat and dead cat). It makes zero sense that the cat would split in two, and the experimenter (and rest of the universe) won't.

Gibbo73
11-17-2011, 10:28 AM
If you put a cat in a box against its will, you'll hear it lol.

The cat Schrödinger used must have been very passive. Or drugged.

I know that cat is alive because the ♥♥♥♥ing thing is screaming that it is in the box!

bluz74
11-17-2011, 10:35 AM
This is why the "Cat-in-the-Box" was never a big seller.

marie pavie
11-17-2011, 10:43 AM
This is why the "Cat-in-the-Box" was never a big seller.
“'Have no fear, little fish,'
Said the Cat in the Hat.
'These Things are
good Things.'
And he gave them a pat."

TangledThorns
11-17-2011, 10:51 AM
Ugh, physic students showing off what they learned.

AlecJ32
11-17-2011, 10:53 AM
Also, it was told between two physicists who agreed that cats are observers too.

Which is why when you put a cat in a similar such box, kitty either goes bye bye or kitty doesn't. Nothing magical happens.

Gibbo73
11-17-2011, 10:58 AM
So the cat stayed silent? BS! That cat would've wailed like a new born baby.

What they should've used was a honey badger. They might as well have lol.

This experiment is stupid. You put the cat in alive then it will be alive when you 'observe' it. ♥♥♥♥ing stupid hippies doing drugs.

marie pavie
11-17-2011, 11:01 AM
Also, it was told between two physicists who agreed that cats are observers too.

*internet meme's as misunderstand genius (http://4.bp.blogspot.com/_6xoH967aC00/TLsx5lqoGFI/AAAAAAAAaxk/sa7x2ZuYGzU/s400/cat084.jpg)*

Dmytry
11-17-2011, 11:04 AM
Which is why when you put a cat in a similar such box, kitty either goes bye bye or kitty doesn't. Nothing magical happens.
Cat being an observer doesn't resolve questions how it would work with a sleeping cat, or a pigeon, a cockroach, an amoeba.
Something magical happens here - the atom was in 2 states at once, then the bunch of atoms in the Geiger counter was in 2 states at once, but at some point the laws broke down and you ended up measuring 1 state.
There's really only two ways that sane physicists view it. One guess is that objects above certain mass collapse into one state due to some non-linearity, perhaps related to gravitation, and the other guess is that it goes all the way and you eventually end up with 2 universes, one with dead and other with alive cat. The less sane physicists have a bunch of crank views involving sentient observation making the two states into one, and also a lot of physicists don't view this issue in any way.

bluz74
11-17-2011, 11:05 AM
I hope they buried the cat under some litter.

IcarusNine
11-17-2011, 11:06 AM
Can you imagine if we applied superposition to statistics?

The car insurance is both paid and unpaid until you get in an accident.

bluz74
11-17-2011, 11:08 AM
What about being a virgin/non-virgin?

Minago
11-17-2011, 11:20 AM
i don't believe if you put monkeys in a room full of typewriters that eventually they would type out war and peace .

edit: and even if they did ,who cares?

schrodinger cat theory is invalid .

surreal
11-17-2011, 11:32 AM
Cat being an observer doesn't resolve questions how it would work with a sleeping cat, or a pigeon, a cockroach, an amoeba.
Something magical happens here - the atom was in 2 states at once, then the bunch of atoms in the Geiger counter was in 2 states at once, but at some point the laws broke down and you ended up measuring 1 state.
There's really only two ways that sane physicists view it. One guess is that objects above certain mass collapse into one state due to some non-linearity, perhaps related to gravitation, and the other guess is that it goes all the way and you eventually end up with 2 universes, one with dead and other with alive cat.

A large enough set of quantum particles obeys to Ehrenfest theorem.
There's nothing more to it.

monkeedude1212
11-17-2011, 12:19 PM
There's really only two ways that sane physicists view it. One guess is that objects above certain mass collapse into one state due to some non-linearity, perhaps related to gravitation, and the other guess is that it goes all the way and you eventually end up with 2 universes, one with dead and other with alive cat.

I've always found the latter to be a bit cooky and disturbing. I mean, think of all the possible actions you could perform right now, and everything you do is governed by the chemistry in your brain which is governed by molecular interactions which are influenced by Quantum Physics... It would suggest that every possible decision you ever make each individual moment creates a next to infinite amount of parallell universes. And this happens for each and every individual. I think Star Trek TNG played with this idea in one episode once, where worf gets slipped into a parallel universe where he was in a relationship with Deanna or something.

What this also suggests is that come Christmas morning in some alternate universe, me and my brother go nuts and start making out, since going insane is a possibility that would be influenced by quantum physics.

For whatever reason, I find determinism more comforting than that. You can take my free will, so long as I get to choose what I'm doing ;)

I've also never understood what any of this has to do with String Theory, but string theorists bring it up a lot, as if it somehow validates their own cooky theories.

Psychrophile
11-17-2011, 12:28 PM
I've always found the latter to be a bit cooky and disturbing. I mean, think of all the possible actions you could perform right now, and everything you do is governed by the chemistry in your brain which is governed by molecular interactions which are influenced by Quantum Physics...It's actually more profound than you're making it out to be. This goes beyond just your experiences and interactions. See below.*

It would suggest that every possible decision you ever make each individual moment creates a next to infinite amount of parallell universes. And this happens for each and every individual.*Not just every individual: every single event that has ever taken place.

What this also suggests is that come Christmas morning in some alternate universe, me and my brother go nuts and start making out, since going insane is a possibility that would be influenced by quantum physics....are you equating homosexuality with insanity?

That aside, yes, it does.

For whatever reason, I find determinism more comforting than that. You can take my free will, so long as I get to choose what I'm doing ;)Do you normally base your beliefs on what's comforting, or what feels good?

Gibbo73
11-17-2011, 12:41 PM
It's a load of ♥♥♥♥♥♥♥♥.

If he puts a cat in a box with some poison then it's anyone's guess if the cat is alive or dead. A guess.

And that's what life is all about.

monkeedude1212
11-17-2011, 12:45 PM
It's actually more profound than you're making it out to be. This goes beyond just your experiences and interactions. See below.*

*Not just every individual: every single event that has ever taken place.


Yeah, I know. It's unfathomable. Everything ever from every instantaneous moment In the entire universe.


...are you equating homosexuality with insanity?


No, well, maybe homosexual incest, but for both me and my brother it is so far outside the realm of whats normal it would be considered crazy.


Do you normally base your beliefs on what's comforting, or what feels good?

Yeah, I do. I personally believe that enjoying life is more important that solving it's mysteries, not to say that I don't get excited when one of them is solved.

It helps create a sense of tolerance for me as well. It's alright if fundies are wrong, so long as they're happy.

frogsmoothy
12-11-2011, 10:18 AM
Do you normally base your beliefs on what's comforting, or what feels good?

You don't?

Nooh
12-11-2011, 10:23 AM
You don't?

The truth, at any and all costs.

But I find the various multiverse theories a bit... too much. I mean, some of them would be impossible to prove, ever.

marie pavie
12-11-2011, 10:33 AM
So some egghead sticks a cat in a box more than 75 years ago, & we're 'sposed to imagine this cat is still alive? Maybe if it was one a Tutankhamun's cats, or Highlander: The Cat, but my money's on a box full of bones.