In standard ΛCDM with simple single-field inflation, the primordial density field is expected to be extremely close to Gaussian, so non-Gaussian signatures in large-scale structure should arise mainly from late-time gravitational evolution and galaxy bias (Desjacques & Seljak 2010; Verde 2010). LSS surveys reveal higher-order clustering statistics, bispectrum shapes, and scale-dependent biases that are difficult to reconcile cleanly with a single-parameter f_NL description plus standard nonlinear growth.
The standard model with single-field inflation predicts essentially zero primordial non-Gaussianity (|f_NL| near zero), so any LSS non-Gaussianity must come from late-time evolution. Recovering the observed scale-dependent bispectrum shapes within the model requires multi-field inflation or non-standard galaxy-bias structure, neither of which is parsimonious.
SCT replaces the hot-dense-center with a superluminal collision and the thermalized debris field. From this single change, primordial perturbations come from a finite multi-stage cascade rather than continuous quantum vacuum fluctuations. The cascade ran through roughly N_coll ≈ 10⁴ independent collision events (P22, P36, P37) before terminating at sub-luminal velocities (P38, P40). Central Limit Theorem applied to that finite ensemble yields a nearly Gaussian primordial field with corrections of order 1 / √N_coll ≈ 10⁻².
Different cascade stages deposit perturbations at different characteristic scales, so the resulting non-Gaussianity is scale-dependent rather than scale-invariant. The bispectrum amplitude varies smoothly with k, peaking near scales corresponding to dominant cascade stages. Single-parameter ΛCDM f_NL templates cannot capture this scale-dependence; the bispectrum-shape mismatches LSS surveys report are direct fingerprints of the finite-cascade origin. Angular-momentum inheritance (P31, P32) adds J-axis-directional correlations between bispectrum modes oriented relative to the cascade axis.
The same M2 framework that produces the bispectrum scale-dependence in the CMB (recid 27) produces the LSS bispectrum signature, simply read out by different observables. The scale-dependent bias hints in galaxy clustering surveys are part of the same scale-dependent f_NL(k) structure inherited from the cascade-stage ladder. There is no need for multi-field inflation or non-standard galaxy-bias physics.
If precision DESI + Euclid + LSST multi-tracer bispectrum analysis finds f_NL(k) is scale-invariant at the 0.5% level (no cascade-stage-correlated structure), the M2 finite-cascade prediction is refuted. Equivalently, if the cosmological |f_NL| is found to be exactly zero at the 10⁻² level (consistent with strict single-field inflation), the cascade-origin signature fails.