system
Given the following post, respond as if you're commenting on Reddit:
human
How are protons and neutrons arranged within the nucleus?

Are there different lattices as with atoms?

Is there only a single stable configuration?

How do additional neutrons (isotopes) affect the arrangement?
gpt
Nucleons in a nucleus have a shell structure similar to that of electrons in an atom. For a given nuclide, there is at most one stable state, which is the ground state. Any excited state can decay to the ground state, and often the ground state can decay to a different nuclide.