Sub-Atomic Particles are Points

Created by Grok

Classical physics portrays subatomic particles as being like snooker balls—hard spheres with a charge. In this model, known as the Bohr model, the nucleus of an atom is made up of positively charged protons and chargeless neutrons. Negatively-charged electrons whizz around the nucleus, so the whole arrangement is like a mini solar system. Electrons when they move are what constitute an electric current, and an electrical generator simply "pumps" electrons. Electrons are also what are involved in chemical reactions: e.g. when hydrogen and oxygen combine to make water, or sodium and chlorine react to form sodium chloride, common table salt. The inner nucleus doesn't get involved in chemical reactions, only nuclear reactions. In reality however, the Bohr model is overly simplistic and was upgraded in the mid-1920s with the development of the quantum mechanical model of the atom. Electrons exist in orbitals or regions of variable probability, rather than orbits where their position can be predicted like a planet orbiting the Sun. Also, subatomic particles are point-like entities, in the mathematical sense. So they have no dimensions. In a "Honey, I Shrunk the Kids" scenario, you wouldn't be able to see such particles. In any case, light doesn't "work" at such small dimensions because wavelengths in the visible spectrum are too long, hence the reason why we use scanning electron microscopes to see very small things such as viruses; optical microscopes just don't work. 

Although they don't have a volume, these particles have mass. They also have a "sphere of influence"; a range over which they interact with other particles via electric and nuclear fields. In a sense, because they have a finite mass but no volume, their densities are infinite. However, that issue is conveniently "parked", just like division by zero in mathematics..