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arXiv · 2607.09395

Sixteenfold Classification of Many-Body Multipoles from Rotation-Compatible Canonical Symmetries

Shingo Kuniyoshi·Rikuto Oiwa·Satoru Hayami
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Abstract

The conventional multipole framework provides a standard symmetry-based language for one-body electronic degrees of freedom, but fails to distinguish physically distinct sectors in many-body operator space. We show that canonical symmetries compatible with rotations provide this structure through two additional 2 labels associated with the particle-number gauge transformation G{\pi}/2 and the particle-hole transformation CA. These labels separate operators with different body numbers and particle-number changes, leading to a sixteenfold classification that organizes selection rules for nonzero expectation values, induced multipoles, and symmetry-allowed couplings in many-body multipole space.

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Shingo Kuniyoshi, Rikuto Oiwa, Satoru Hayami. 2026-07-10. Sixteenfold Classification of Many-Body Multipoles from Rotation-Compatible Canonical Symmetries. https://arxiv.org/abs/2607.09395

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