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arXiv:2606.17148

Quantum Resources and Wigner Symmetry in Nucleon-Nucleon Scattering from Effective Field Theory

Ian Low, Thomas R. Richardson, Sokratis Trifinopoulos

nucl-thhep-phquant-phSubmitted Jun 15, 2026• Announced Jun 17, 2026• 0 citations
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Abstract

We study quantum resources in the spin degrees of freedom, such as entanglement, stabilizer magic, and non-local magic, in low-energy nucleon-nucleon scattering through next-to-leading order in pionless effective field theory. Treating each nucleon spin as a qubit, we calculate the corresponding resource-generating powers of the scattering operator at generic center-of-mass momentum and scattering angle $Θ$. The analysis retains $S$- and $P$-wave channels generated by two-derivative contact interactions. When the microscopic physics exhibits Wigner's $SU(4)$ spin-flavor symmetry, the neutron-proton amplitude becomes proportional to the spin-space identity operator and therefore generates no new resources after scattering, extending an observation previously made for leading-order $S$-wave scattering. The same-nucleon channel remains resource-generating because constraints from identical particles project out part of the Hilbert space. These results show how enhanced symmetries, partial-wave structure, and resource generation are intertwined in low-energy two-body scattering.

Comments
12 pages, 3 figures

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