I'm not sure whether to post this here or not, but since the book is about quantum i figured it was as good a place as any. I don't know too much about this, so I am just trying to understand exactly what the heck Feynman was talking about. I understood most of it but I have a few questions I was hoping some of you guys here could help me out with. So here are my questions:(adsbygoogle = window.adsbygoogle || []).push({});

Is Feynman saying that the reason why we use quantum mechanics is to be able to talk about the possibility of an action rather than the cause of it? E.g. that a photon will interact with an electron with some probability, but not why the photon is reacting in the first place?

Second, are the photons which bind electrons to nuclei 'virtual' and if they are, what does he mean by this? If they don't exchange actual photons, why is he using this as an explanation for what is occurring?

Finally, Why did he choose to have a rotating stopwatch hand as the means of choosing the angle at which the probability amplitude points?

I think this stuff is really interesting, so i'd like to understand it as well as possible. Thanks for the help =)

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# Qed and probability

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