Can someone explain to me what's the Schrodingers cat?

[DeltaForce]

Hi, I'm new to this thread. My brother tried to explain the Schrodinger's cat to me but the explanation was vague, I became confused. Can someone explain to me in high schooler language what it is and how it works? Thanks in advance.

 

[berkeman]

Have you tried looking on Wikipedia or at other sources (that may be more clear than your brother)? Try reading through the Wikipedia article and then ask any specific questions you still may have?

https://en.wikipedia.org/wiki/Schrödinger's_cat

 

[StevieTNZ]

Hi, I'm new to this thread. My brother tried to explain the Schrodinger's cat to me but the explanation was vague, I became confused. Can someone explain to me in high schooler language what it is and how it works? Thanks in advance.

A good book in general, to get an understanding of quantum mechanics which underpins the cat thought experiment, is 'Sneaking a Look at God's Cards' - https://www.amazon.com/dp/069113037X/?tag=pfamazon01-20&tag=pfamazon01-20

 

[DennisN]

My brother tried to explain the Schrodinger's cat to me but the explanation was vague, I became confused. Can someone explain to me in high schooler language what it is and how it works? Thanks in advance.

I will give it a try with the help of a Sixty Symbols video.

In quantum mechanics, objects can be in a so-called superposition of states, which is sort of a mixture of different states. However when they are measured, i.e. interacts with the environment, objects are found to be in a particular state and never in a mixture of states. The process of going from a superposition to a particular state is called wave function collapse. The Schrödinger's cat, which is a thought experiment, is taking this idea up to a macroscopic level (which in the case with the cat can not be done in reality¹) in order to describe the counterintuitive process of going from a superposition of states to a particular state.

¹ Nowadays, there are however a number of experiments that have managed to put large objects in superposition, though the objects have not been as large as cats.

Here is a video from Sixty Symbols about the Shrödinger's cat thought experiment:

 

[DennisN]

1 Nowadays, there are however a number of experiments that have managed to put large objects in superposition, though the objects have not been as large as cats.

And here is an example of such an experiment:

Article: Quantum effect spotted in a visible object (PhysicsWorld)
Paper: A. D. O’Connell et al, Quantum ground state and single-phonon control of a mechanical resonator (Nature volume 464, pages 697–703 (01 April 2010))

 

[StevieTNZ]

I will give it a try with the help of a Sixty Symbols video.

In quantum mechanics, objects can be in a so-called superposition of states, which is sort of a mixture of different states. However when they are measured, i.e. interacts with the environment, objects are found to be in a particular state and never in a mixture of states. The process of going from a superposition to a particular state is called wave function collapse.

Please do note that decoherence, which is the system (e.g. the cat) interacting with the environment, is in principle still in a superposition. That means in the thought experiment, the cat is NOT either dead or alive after decoherence, rather, as quantum mechanics predicts, a superposition of alive and dead.

 

[bhobba]

Please do note that decoherence, which is the system (e.g. the cat) interacting with the environment, is in principle still in a superposition..

The cat is not in a superposition - it is in a mixed state. It is entangled with the radioactive source. The system radioactive source and cat is in a superposition, but each part is in a mixed state.

Thanks
Bill

 

[martinbn]

Here