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However, the scientist is actually one light minute away. When does the particle go from being distributed to being in one location? When the scientist actually receives the information, or when the computer records it? Also, what if the scientist isn't there to receive the information, does the electron stay distributed?
As far as I know, neither. The concept of the experimenter's perception of the particle's location, and the actual location of the particle, are 2 different things. By and large, they are exactly the same. But because most of the things that QM deals with are empirically unverifiable by current technology, we can never be completely certain.
A very simplistic parallel is this: if you ask somebody where Jane is, he can say: "she's at school", or "at Starbucks". Jane's exact geographic coordinates are not the same information as "at school", and unless she has a GPS tracker, you are unable to ascertain that Jane is indeed at coordinates (x, y, z). So you have an integral (roughly, the volume occupied by the school), which, if you think about closely, are quite similar to the uncertainties that QM has about mass. Obviously Jane cannot be everywhere in school at once, and, given that she's moving around, you cannot know for sure that she is in that exact same spot as she was before. Thus we have the analogous concept of the distribution of the location of
where the particle is likely to be.
So Jane did not "go from being distributed to being in one location" contingent upon your receiving of the information that she is "at school" (or otherwise). Jane is where Jane is; what you know of her whereabouts is entirely another matter.
I know you weren't responding to me but that's a pretty good example, so thanks for that. Makes things a bit clearer.
19 Jan 2012, 6:09 pm
