Exact symmetry and symmetry-breaking phenomena play a key role in gaining a better understanding of the physics of many-particle systems, from quarks and atomic nuclei, through molecules and galaxies. In nuclei, exact and dominant symmetries such as rotational invariance, parity, and charge independence have been clearly established. Beyond such symmetries, the nature of nuclear dynamics appears to exhibit a high degree of complexity, and only now, we show the fundamental role of an emergent approximate symmetry in nuclei, the symplectic Sp(3,ℝ) symmetry, as clearly unveiled from ab initio studies that start from realistic interactions. In this article, we detail and enhance our recent findings presented in [T. Dytrych, K.D. Launey, J.P. Draayer, D.J. Rowe, J.L. Wood, G. Rosensteel, C. Bahri, D. Langr, R.B. Baker, Phys. Rev. Lett. 124, 042501 (2020)], that establish Sp(3,ℝ) as a remarkably good symmetry of the strong interaction, and point to the predominance of a few equilibrium nuclear shapes (deformed or not) with associated vibrations and rotations that preserve the symplectic Sp(3,ℝ) symmetry. Specifically, we find that the structure of nuclei below the calcium region in their ground state, as well as in their low-lying excited states and giant resonances, respects this symmetry at the 60–80% level.

精确的对称性和破坏对称性的现象在更好地理解从夸克和原子核到分子和星系的多粒子系统的物理过程中起着关键作用。在原子核中，已经明确建立了精确的和占优势的对称性，例如旋转不变性，奇偶性和电荷独立性。除了这种对称性以外，核动力学的性质似乎表现出高度的复杂性，只有到现在，我们才显示出原子核中出现的近似近似对称性（辛Sp（3，ℝ）对称性）的基本作用，如从ab中明确揭示的那样。从头开始从现实的互动开始的研究。在本文中，我们详细介绍并增强了[T. Dytrych，KD Launey，JP Draayer，DJ Rowe，JL Wood，G。Rosensteel，C.Bahri，D.Langr，RB Baker，Phys。牧师 124，042501（2020）]，即建立SP（3，ℝ）作为强相互作用的显着良好的对称性，并指向几个平衡核的形状与相关联的振动和保持旋转的优势（变形或不）辛Sp（3，ℝ）对称。具体来说，我们发现在钙基区域以下的核结构，在其基态，低激发态和巨共振下，在60-80％的水平上都尊重这种对称性。