Understanding the Symmetric Mass Generation in Lattice-QCD

Signatures of symmetric mass generation (SMG) have recently been reported in lattice QCD calculations employing staggered fermions. We discuss the general criteria for SMG, and demonstrate that these conditions are indeed met by the staggered fermion action, in particular by the continuum action derived by Lee and Sharpe. We propose possible RG flow around the SMG transition, guided by the numerical results. We also point out that the Goldstone tetraquark meson states provide a phenomenological signature of the "type-II" SMG phase.