Structural Cosmology v3.3: Observational Forecasts From Structural Field Δ to Future Observational Signatures

Structural Cosmology v3.3 establishes the observational forecasting layer of the Structural Cosmology framework, connecting the Structural Field Δ(x,τ) to future cosmological observables through scale-dependent Projection Operators Πᵍˣ(k,z). Building upon the Effective Field Theory formulation (v2.x), Cross-Scale Consistency (v3.2), and the Structural Bandwidth Principle (v3.1), this work develops an illustrative forecasting framework spanning six major survey platforms: Euclid, Rubin Observatory/LSST, DESI, SKA, CMB-S4, and LISA. The framework introduces projection-based mappings from structural dynamics to observable quantities including galaxy clustering, weak lensing, 21cm intensity mapping, CMB anisotropies, and gravitational-wave observables. New contributions include the Gravitational-Geometric Perturbation Statistic (GGPS), a full multi-probe Fisher forecast framework, and an expanded falsifiability network containing 55 testable connections (C1–C55), including C33 (Gravitational Slip, η ≠ 1). One illustrative prediction explored within the framework is the Geometry-Growth Projection Test (GGPT), corresponding to a potential suppression of Δ(fσ₈) ≈ −5% to −7% around z ≈ 1.0–1.5 relative to ΛCDM. This prediction is presented as an illustrative forecast and has not been fitted to observational data. The release contains: Full v3.3 observational forecast paper (20 figures) Survey-specific forecast frameworks Multi-probe Fisher analysis Cross-scale consistency diagnostics (CSCI, EG, GGPT, GGPS) Halo mass function forecast framework Detection and feedback pipelines Updated falsifiability network C1–C55 Zenodo-ready reproducible Python demonstration code All forecasts are illustrative and intended as a conceptual framework for future observational testing rather than calibrated cosmological predictions.