bigbounce/spin-torsion cosmology research program
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PredictionsGalaxy Bispectrum fNL

Galaxy Bispectrum fNL

The decisive bounce-vs-inflation discriminator. The matter bounce predicts fNL = -35/8 = -4.375, parameter-free and mechanism-independent across all matter bounce variants. Inflation predicts |fNL| < 1. One measurement settles the question.

FLAGSHIP
fNL = -35/8 = -4.375
Matter bounce (all variants)
SPHEREx (~2028)
Current Constraint

σ(fNL) ≈ 4.1 (Planck + DESI combined, external). Our DESI multi-tracer central forecast: 9.4% improvement (empirical α, consistent with no improvement at <). SPHEREx forecast: 2.6– conditional detection if fNL = -4.375.

Key Results
  • fNL = -35/8 derived across 3 bounce models (mechanism-independent, parameter-free)
  • Current Planck alone: σ ≈ 5.1, fNL = -0.9 ± 5.1
  • Combined Planck + DESI: σ ≈ 4.1 (our -4.375 at ~1.1σ)
  • Multi-tracer central forecast: 9.4% improvement from AI-purified DESI anomaly tracers (consistent with no improvement at <)
  • SPHEREx (~2028) will measure to σ ≈ 0.7-1.0 → 2.6- conditional detection
  • Triple role: galaxy bispectrum + PBH abundance regulator + induced GW shape