General talking about Quantum Mechanics —— 普及一下量子力学

Because atomic behavior is so unlike ordinary experience, it is very difficult to get used to, and it appears peculiar and  mysterious to everyone — both to the novice and to the experienced physicist. Even the experts do not understand it the way they would like to, and it is perfectly reasonable that they should not, because all of direct human experience and of human intuition applies to large objects. We know how large objects will act, but things on a small scale just do not act that way.  So we have to learn about them in a sort of abstract or imaginative fashion and not by connection with our direct experience … We would like to emphasize a very important difference between classical and quantum mechanics. We have been talking about the probability that an electron will arrive in a given circumstance. We have implied that in our experimental arrangement (or even in the best possible one) it would be impossible to predict exactly what would happen. We can only predict the odds! This would mean, if it were true, that physics has given up on the problem of trying to predict exactly what will happen in a definite circumstance. Yes! physics has given up. We do not know how to predict what would happen in a given circumstance, and we believe now that it is impossible — that the only thing that can be predicted is the probability of different events. It must be recognized that this is a retrenchment in our earlier ideal of understanding nature. It may be a backward step, but no one has seen a way to avoid it … So at the present time we must limit ourselves to computing probabilities. We say "at the present time," but we suspect very strongly that it is something that will be with us forever — that it is impossible to beat that puzzle — that this is the way nature really is.

 

Richard P. Feynman, Robert B. Leighton, and Matthew Sands