- #1

paka

- 3

- 0

1. Feynman says that if we don't measure which hole a certain electron is going through and just observe the probability distribution graph of many such electrons, they make the interfernce pattern. But if we do measure it, then it becomes a normal additive probability graph of the probability distr. of the two slits' separate graphs. i understand that 'measuring' by shining light on it for example disturbs the elctron's path, but why should it be disturbed in such a way only that the new behaviour is similar to a particle's? why shouldn't the distr. just become more random?

2. is it true that a single electron also, if not disturbed or measured as to which hole it went through in any way, will interfere with itself? In that case the interference is not visible, because the electron will be detected only at a single point on the screen. how can we be sure now that it is showing wave nature, it cud just as well be a particle, getting deflected randomly to where it was detected. From what i understand of wave nature, if there is interference,there shud be lots of detections with maximas and minimas, even wid a single electron. Now on the contrary if we say that a single electron behaves like a particle, then there isn't any reason why all the other e- sent after it shouldn't do the same, and hence why a normal, interference-free pattern shouldn't be formed. sorry if this sounds stupid, I am terribly confused.

3.what does the imaginary part of the probability amplitude signify? Can anyone please explain what it is and what relation it has, or not with the many-worlds theory?

4.Feynman cites the uncertainty principle when saying that it is not possible to simultaneously know which slit the e- went thru and still observe the interference pattern in the prob. distr.. I know what the Hburgs' UP is, but i couldn't grasp how exactly it could be related with this. Of course there is the same you can't know one thing accurately while knowing the other, but how does momentum and position come into the slit experiment? Please help.

5. Feynamn says that when the observer observes which hole the e- went thru, its wavefunction collapses and the obs. and e- are now entangled. I am sorry, bt what the heck is that supposed to mean?

Many thanks in advance!