CMB Without Expansion

The cosmic microwave background is often taken as definitive evidence for universal expansion. No static framework has yet reproduced its exact blackbody spectrum under known physical conditions. This study extends the companion paper Redshift Without Expansion by applying a frequency-independent redshift mechanism within a Liouville formulation. The kinetic redshift operator preserves a perfect Planck spectrum, maintains μ = 0, and yields T ∝ K−1 with an identical temperature–redshift relation T (z) = T0(1 + z) consistent with measurements from COBE and FIRAS. Photon number and energy densities evolve as ˙nγ = −3Heff nγ and ˙ργ = −4Heff ργ , where Heff = ˙K/K represents an effective Hubble parameter without metric expansion. The result establishes an observational degeneracy between kinetic redshift and geometric expansion while predicting a measurable secular temperature drift ˙T /T = −Heff ≈ −2.3 × 10−18 s−1. The framework provides a static, falsifiable pathway for examining the cosmic microwave background without reliance on expanding-space assumptions.