Symmetries of many-body systems are well understood but in some respects are assumed. The existence of magic numbers in atoms and nuclei suggest the existence of shells, and those are ascribed to angular momentum. In this talk, we consider the emergence of such symmetries with respect to the underlying local, finite range, potentials responsible for the dynamics of the system. In other words, why shells? Implications regarding realistic systems will be discussed.

Videoconference via https://us02web.zoom.us/j/88990497990