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Name: Maja
Status: student
Grade: 9-12
Country: Denmark
Date: April 4, 2011


Question:
I would like to understand the thing about Schrödingers cat. Is it really alive and dead at the same time? I talked to a friend, who said it is actually a lie, that the life of the cat would depend on, if we look at it or not, and that the truth is, that we just do not KNOW if it is alive or dead, and that's why we just say it is both, though it is not true. Is that right?



Replies:
The cat is a thought experiment to illustrate the uncertainty principle. Until we look, we are not sure whether the cat is still alive or the isotope has decayed and the cat has died. In essence the cat is alive/dead (it can be either) until we take a look that is, make a measurement.

R. W. "Bob" Avakian


Hi Maja

Actually, the story about Schroedinger's cat is a thought experiment whose purpose is to cast sarcasm on a proposed outcome in quantum mechanics.

Quantum mechanics suggests that a light quanta does not reveal itself as a particle or as a wave until it is observed and prior to observation, the light quanta existed only as a probability.

So Schroedinger (and Einstein who also later agreed with him) compared this situation to a cat in a box. There would be in the box with the cat a completely random trigger that would cause the cat to live or die to the point that no one knows if the cat was alive or dead until they opened the box. However, Schroedinger points out that the cat, if it was alive, would have a memory of sitting in the box and therefore this quantum mechanics outcome is absurd.

Sincere regards, Mike Stewart


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