Finite Residence, Feasibility Projections, & Quartic Transport

When a state-dependent feasibility projection acts on the constitutive stress tensor and places the first-order shear operator in its nullspace, the k² diffusive pole is structurally forbidden—not parametrically suppressed. The leading admissible relaxation shifts to k⁴ via a Burnett-type operator, with k³ excluded by stress tensor symmetry σ_ij = σ_ji. The selection rule Π_x[σ_ij] = 0 is an operator-level statement whose dynamical realization is the finite residence of balanced Navier–Stokes states: DNS shows these configurations are crossed but not occupied, with escape occurring preferentially through loss of recursive coherence rather than collapse of stretching. The mechanism unifies independent k⁴ observations across non-relativistic Lifshitz holography (where bulk couplings cancel k² contributions), fracton and dipole-conserving fluids (where enhanced symmetry constraints forbid first-order kinetics), and photonic quasicrystal spectral reorganization under irrational projection methods. The analysis situates quartic transport within constraint geometry as a transport-sector instantiation of the curl-maintenance floor established in the geometry of self-correction.