The chapter 2 section 4 of volume 1 is on nuclei and particles.
Here are a few things that trouble me. Dr. Feynman says that
Another most interesting change in the ideas and philosophy of science brought about by quantum mechanics is this: it is not possible to predict exactly what will happen in any circumstance. For example, it is possible to arrange an atom which is ready to emit light, and we can measure when it has emitted light by picking up a photon particle, which we shall describe shortly. We cannot, however, predict when it is going to emit the light or, with several atoms, which one is going to. You may say that this is because there are some internal "wheels" which we have not looked at closely enough. No, there are no internal wheels; nature, as we understand it today, behaves in such a way that it is fundamentally impossible to make a precise prediction of exactly what will happen in a given experiment.
Has this statement changed at all? He says that there are no internal wheels. At one point I also remember him mentioning that we do not know what is going on inside a nucleus. Is this still true?
One more extract is this:
just like with a field of interaction between charges and photons, we made quantumelectrodynamics, with a field of interaction between neutrons and photons, we can make quantum'NUCLEO'dynamics
He later mentioned that the calculations are going on for 20 years and are too complicated to solve. What about this theory? Has it been proven or disproven? Or are we still not capable of calculating it?
The last thing that bothers me with this chapter is this:
So we are stuck with a theory [he is talking about the pion and mesons etc.], and we do not know whether it is right or wrong, but we do know that it is a little wrong, or at least incomplete. While we have been dawdling around theoretically, trying to calculate the consequences of this theory, the experimentalists have been discovering some things. For example, they had already discovered this m-meson or muon, and we do not yet know where it fits. Also, in cosmic rays, a large number of other "extra" particles were found. It turns out that today we have approximately thirty particles, and it is very difficult to understand the relationships of all these particles, and what nature, wants them for, or what the connections are from one to another.
Is this condition still the same? Have we tied the loose ends together yet? Or do we still not know what these particles do?
What is the prevailing theory currently about these particles?