What is the difference between atomic physics and nuclear physics?

Asked by: Kelley D. Burroughs

Answer

Atomic physics is mainly concerned with the electrons orbiting the nucleus of an atom. In this regime the Coulomb interaction dominates and phenomena can be explained by quantum electrodynamics (QED). Nuclear Physics on the other hand, concerns itself with the particles of the nucleus called nucleons (protons & neutrons). In the nucleus there is Coulomb repulsion between the protons but there is also the strong force which keeps the nucleus together. This interaction is not completely understood but there are many models to address it. In the nucleus the leading theory is quantum chromodynamics (QCD) which attempts to explain phenomena in terms of quarks which are the particles that are proposed to make up the nucleons.
Answered by: Pete Karpius, Physics Grad Student, UNH, Durham