SU(3) versus deformed Hartree-Fock

Deformation is fundamental to understanding nuclear structure. We compare two ways to efficiently realize deformation for many-fermion wavefunctions, the leading SU(3) irrep and the angular-momentum projected Hartree-Fock state. In the absence of single-particle spin-orbit splitting the two are nearly identical. With realistic forces, however, the difference between the two is non-trivial, with the angular-momentum projected Hartree-Fock state better approximating an ``exact'' wavefunction calculated in the fully interacting shell model. The difference is driven almost entirely by the single-particle spin-orbit splitting.