Do protons, neutrons or electrons have the smallest mass?
1 Answer
I think what your asking is whether or not you can get smaller masses than an electron, proton or neutron. The answer is yes.
Explanation:
Protons, neutrons and electrons are sub-atomic particles. Electrons actually behave as waves as well as particles but do still have a mass (it is just very small compared to a proton or neutron).
Einsteins equation
The smallest particles to have a 'mass' as we conventionally think of a mass are neutrinos. There is some debate as to whether they have a mass, but recent data suggests they do. It is just VERY small. Neutrinos are intact incredibly common but just incredibly hard to detect because they have very little interaction with matter.