Planck's initial conditions evolved forward predict S₈ = 0.832 +/- 0.013; the late universe measures 0.759 to 0.776 across KiDS, DES, and HSC, a 2-to-3.4σ deficit echoed by SZ cluster counts. The escapes are blocked: the required hydrostatic bias is implausible against lensing calibrations, the needed neutrino masses are excluded, modified gravity pushes the wrong way, and the suppression concentrates at late times in a shape no uniform mechanism produces.
The model assumes every gravitational signal at late times is produced by matter alone clustering under GR: the lensing sky must equal the matter sky. If part of the observed signal has a different source, the CMB-normalized forecast inherits it as phantom matter clustering, and the late universe will forever measure smoother than the forecast, exactly as observed.
SCT replaces the dark matter particle with coherence: comoving baryonic structures gravitate constructively, amplifying the effective signal by A(N, σ_v, R), and the inferred clustering amplitude scales as sigma8_inferred = A^(1/2) × sigma8_true (Paper 6, Equation 20). The CMB-era sky is coherence-free (A of 1 at recombination), so Planck's normalization silently books the later mesh contribution as matter; evolved forward, the forecast overshoots what matter alone ever does, and every late-time probe reads the difference as a deficit. The framework's derived value lands where the surveys do: S₈ = 0.783 +/- 0.015 from the cosmological coherence background, against the measured 0.76 to 0.78.
The redshift shape is the signature: amplification grows as structure virializes, A(z) climbing from 1 toward 5.85 today (P50, P52), so the apparent deficit grows toward z of 0, the observed kink, and the same growth produces the gamma = 0.633 growth-index excess, the lensing-is-low offsets, and the SZ-count mass bias through one bookkeeping error in one direction.
Three premises carry the mechanism, and the family it resolves spans six named tensions: coherence amplification, misread as matter, then missed when matter alone is forecast. There is no need for implausible mass biases or excluded neutrinos.
The registered kill: the tension must shrink with redshift, the S₈ deficit falling from about 0.05 at z of 0.3 to under 0.01 by z of 1.5 as A(z) recedes; Euclid and Rubin measuring equal-magnitude tension at z of 1.5 falsifies the coherence mechanism and hands the problem to neutrinos or early dark energy. The derived 0.783 carries its own blade: a settled S₈ outside 0.738 to 0.828 breaks the coherence-background prediction.