
the answer
Whew! These are not the sort of questions one can rattle off tidy answers for; more like, "Take the following courses for a start...." But the questions do seem to be serious and non-"crackpot" so I am inviting Mark Halpern (who teaches 2nd year quantum mechanics at UBC) to take a shot. Many of the answers may be found in my Skeptic's Guide to Physics which I hope you will read. Some of the questions are of the "Come now, common sense dictates..." variety and have no answer that will satisfy anyone who believes that quantum mechanics should ultimately validate common sense. It doesn't. Common sense is wrong, because we and what we can see are too big and too slow to behave the way electrons do. Anyway most of those questions are too hard to answer in a reasonable time; major coursework may be required... In the meantime here are Mark Halpern's answers:
1. B is certainly NOT a description of the world we live in. This sort of hidden complete description comes under the heading "hidden variable theories", and gives predictions for simple experiments which do not occur.
2. I picture these exchange particles spreading out in all directions at once. Their density therefore drops with distance. That is why force strength typically drops off as the inverse of the square of the distance.
3. There are a number of efforts of this sort, but nothing with any real success. At this point, whether this approach might work is anyone's guess.
4. I am not sure I understand the question, but I think that single photons are distributed waves which travel through both slits. In fact they travel all over the apparatus. Any attempt to trace their path disturbs the phase of the part of the path which was checked and removes interference from that part of the pattern.
5. The answer to 1 is not b).
6. But question 5 does not apply to standard quantum mechanical systems.
7. No answer.
8. I never heard this remark, but it is certainly an interesting and important fact that the universe is composed of particles. I remember seeing the films of lectures Feynman gave at Cornell in which he pounds on the board and says, more or less: there you have it. Stuff acts like waves and comes in lumps, and that is the mystery of quantum mechanics.
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