I am! Schroedingers cat is a way of thinking about one of the weirder results in a subject called quantum mechanics.
The idea is that you don’t know what a particle is doing until you look at it, but more than that, before you look at it, it’s doing many different things at the same time!
If the particle is a cat instead, then before you look at it the cat is alive, dead, reciting shakespeare, playing xbox, all at once!
Surely when you look at it you change the particles direction because you wre shining light on it (thats the uncertainty principle isn’t it?), so you can never actually know if it was doing what you see it doing? Does that even make sense or am i speaking rubbish?
Not rubbish at all – very smart in fact! The double slit experiment is a famous example. Imagine you have a beam of electrons hitting a wall with two narrow slits in it. The electrons can pass through the slits and hit another detector behind the slits (photo-paper, flourescent screen, CCD camera… whatever) to leave a pattern. If you have some kind of charge monitor on the slits themselves so you can actually ‘see’ which slit the electrons chose to go through, then they’ll behave like particles and spray dots on the flourescent screen behind… like you would expect. If you DON’T look to see what slit they went through, though, they go through BOTH AT THE SAME TIME and behave like water waves, making a ‘diffraction pattern’ on the flourescent screen! It totally depends on whether you’re looking or not! Crazy quantum shenanigans 👿
So, when scientists say ‘look at’ what we mean is we take a measurement of the particle, which doesn’t mean we necessarily have to shine a light on it. As Scott says, it could mean that we’re counting how many particles go through one gap or the other.
Comments
anon-106860 commented on :
Surely when you look at it you change the particles direction because you wre shining light on it (thats the uncertainty principle isn’t it?), so you can never actually know if it was doing what you see it doing? Does that even make sense or am i speaking rubbish?
Scott commented on :
Not rubbish at all – very smart in fact! The double slit experiment is a famous example. Imagine you have a beam of electrons hitting a wall with two narrow slits in it. The electrons can pass through the slits and hit another detector behind the slits (photo-paper, flourescent screen, CCD camera… whatever) to leave a pattern. If you have some kind of charge monitor on the slits themselves so you can actually ‘see’ which slit the electrons chose to go through, then they’ll behave like particles and spray dots on the flourescent screen behind… like you would expect. If you DON’T look to see what slit they went through, though, they go through BOTH AT THE SAME TIME and behave like water waves, making a ‘diffraction pattern’ on the flourescent screen! It totally depends on whether you’re looking or not! Crazy quantum shenanigans 👿
anon-106860 commented on :
Very crazy! ☺☺
Jim commented on :
So, when scientists say ‘look at’ what we mean is we take a measurement of the particle, which doesn’t mean we necessarily have to shine a light on it. As Scott says, it could mean that we’re counting how many particles go through one gap or the other.