IDTIMWYTIM: Schrodinger's Cat

"I Don't Think It Means What You Think It Means" examines scientific theories that have taken on a life of their own in popular culture & we help you understand what they really mean in scientific terms. Today we take on Schrodinger's Cat, the famous thought experiment by Austrian physicist Erwin Schrodinger.

References for this episode can be found in the Google document here:

[Owiko]

How about Schrodinger's spider? you know the one that you step on, and you arent entirely sure if it is dead or not, until you lift your foot...

[flareart]

I learned this theory from my choir teacher. He said that there was a universe where the cat was alive and a parallel universe where it was dead and every time something happened, ever conceivable outcome formed a parallel universe.

...He then used this concept to tell us, when we messed up, that we could have been in the universe where we sang every note correctly.

[TheErudite]

IDTIMWYTIM: IDTIMWYTIM: Schrodinger's Cat... you're going to have to do this again, because apparently most of the commenters missed this entire part: 2:50 - 3:10

The whole point of this thought experiment is not to see if that cat is alive or dead, or even matters that the cat can observe things too but simply to point out that THERE IS NO UNIFIED THEORY between NEWTONIAN PHYSICS AND QUANTUM PHYSICS. 
There are two different scales at work here, neither of which play well together. Schrodinger was trying to point out that THIS DOES NOT MAKE SENSE and that they are missing a large part of the story here. 

For quantum particles, superposition works. On the Macro scale, it does not work. So, that means you (or rather the scientists back then) need to STOP USING NEWTONIAN PHYSICS TO ARGUMENT OR DESCRIBE QUANTUM PHYSICS and vice versa. .. 

Let's see if that gets across to anyone... >_<

[IrishSnwbrdr]

When they say "observe", it doesn't mean a conscience person has to see the event for it to leave a superposition, observe more nearly means interact. So as soon as one thing interacts with another, it is observed.

[theinnovative]

But the cat can be both alive and dead. It has nine lives, therefore it can lose one and be dead, yet still be alive with 8 lives remaining.

Checkmate, science.

[HalcyonSerenade]

I always used it to mean "the outcome will only be determined once you've observed it, " i.e. the principle that the uncertainty collapses once observed. I always thought of it as an illustration of uncertainty and superposition rather than an illustration of the illogical discrepancies between quantum physics and "normal" physics, even though that's what motivated the thought experiment's inception.

[SyphistPrime]

My friend and I came up with a movie idea where Shrödinger's Cat started a Zombie Apocalypse where the zombies must be observed to be stopped. The movie would contain Einstein, Shrödinger, Isaac Newton, and other various scientists. There would be a lot of math and science jokes and stuff. The idea was pretty hilarious to discuss.

[loganperry]

These people need to understand it before saying, " just put a camera in a box or put it in a transparent box"

[dannyhuang]

What if the cat is experimenting with us and we are only alive when they observe us?

[TheGrahamBrechin]

Okay ... here is a topic.. Cows... yes ... cows can tell when it is going to rain. They lie down and start chewing the cud. WHY? .. when cows eat grass they are also ingestic air @ say 1 atmosphere. The outside atmospheric pressure drops causing moisture in the air to precipitate causing rain. Inside the cows 4 stomachs the air pressure is still at 1 atmosphere, thus making the cow feel bloated. Perhaps this is why cows lie down before rain falls. This should be easily testible by leading a cow into a hyberbaric chamber and slightly lowering the external pressure.  What do you think?

[MetalMarauder]

But wouldn't the cat be observing whether the atoms decay and break the poisonous gas? And therefore there would be no superposition?

[hellsburp]

I asked a librarian if she had a book about Pavlov's dog and Schrodinger's cat. She says it rings a bell but she wasnt sure if it was there or not.

[nobodyknowsforsure]

Dear God - thank you - this was sending me insane how people kept insisting the cat was dead and alive - it's either dead or alive - nothing in between

[majinakuma]

Not even joking I cracked my phone while watching this video I should of have left it on the ground so that it would be broken and not broken at the same time lol

[mikelor]

I tried 4 times to understand this experiment, and only now, after watching this video, my eyes are finally open. Thank you, SciShow . You guys are made of pure awesomness.

[rowanangstadt]

If he superposition can't be observed and collapses once you would observe it, couldn't the cat be considered an observer, thus not allowing the superposition to form at all?

[computerdude]

Schrödinger's Cat walked into a bar.

and Din't

[MrPhatNOB]

This makes the Schrodinger's Cat theory now makes sense to me. Thank you. I also looked at it as the old fashioned 'the cat is either either dead or alive, opening the box makes no difference' but this video shows what was meant by the theory. Excellent job and I appreciate being given the full story, Traditional, Quantum, and the attempted combination of the two.

[InnatelyDone]

The Double Slit experiment - an idea for the "I Don't Think It Means What You Think It Means"

[MrPerfectlogic]

I had a dead cat, I put it in a box. It didn't worked!