Abstract: A fundamental goal in nuclear theory is to obtain an ab initio (“from the beginning”) description of the nucleus, that is, directly from the forces between the nucleons within the nucleus and from the many-body Schrödinger equation. Despite formidable computational challenges, such an approach is now feasible, at least for the lightest nuclei. Beyond simply providing quantitative predictions, a successful ab initio description can also provide qualitative insight into the physical nature of the phenomena arising in these nuclei. Perhaps most intriguing is the question of how collective correlations, which involve cooperative motion of all the nucleons, arise out of the complex interactions of these nucleons.

In this colloquium, we will focus on collective deformation and rotation in light nuclei (in particular, the beryllium isotopes), and on how ab initio calculations confirm the importance of dynamical symmetries in understanding the nature of the many-body correlations underlying these phenomena.