Persistence of the strong-CP minimum in complete hadronic scattering

Establish whether the preference for a vanishing strong CP phase found in certain low-energy neutron–proton scattering calculations persists in a complete hadronic scattering calculation.

Background

The paper cites prior work reporting a local minimum of averaged spin magic at the strong CP phase θˉ=0\bar\theta=0 for selected ranges of the CP-conserving spin interaction in low-energy neutron–proton scattering. The authors explicitly note that the result has not yet been established in a complete hadronic treatment.

References

Whether this preference persists in a complete hadronic scattering calculation remains to be established.

— Quantum Magic and the Strong Coupling Constant  (2610.11121 - Liu et al., 8 Oct 2026) in Section Discussion, footnote to the bullet point “Which SM parameters can the principle explain?”