I'm aware my question may not even make sense when considering quantum physics, but please excuse my ignorance. We are taught in school that there are basically 3 particles that make up atoms (protons, neutrons, electrons) and that broadly for each 1 proton there will be 1 neutron and 1 electron. My question is how do we know that neutrons and electrons are not much smaller particles that just happen to lump together in predictable quantities due to their interactions with protons?
Let's say for instance that for each 1 proton you have 1000 neutrons and 1000 electrons. In this case, each neutron has 1/1000th the mass of a proton and each electron has 1/1000th the charge of a proton. It would seem to me that all the math still works just fine and our observations would still be the same.
We are also taught that you should think of an electron as something like a cloud rather than 1 distinct particle which is very counter-intuitive. In contrast, if 1 electron is really 1000 or a million, it is not just intuitive, but obvious that they would form as kind of cloud around the nucleus of an atom.