Low-Surface-Brightness Cosmology as a Direct Probe of Entanglement-Weighted Operator Geometry: Predictions for the Vera C. Rubin Observatory Era

The Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) will revolutionize low-surface-brightness (LSB) astronomy, providing unprecedented statistics on tidal features, stellar streams, and diffuse light around galaxies. These LSB features encode the interaction history of cosmic structures and serve as direct probes of the underlying gravitational theory. In this work, we develop the mathematical formalism connecting LSB observables to predictions from Entanglement-Weighted Operator Geometry (EWOG), a theory where spacetime emerges from quantum information networks of C-Boson fields. We derive specific, testable predictions for Rubin/LSST measurements, including enhanced diffuse light fractions fdiff(M_*, z), tidal feature probabilities Ptidal(M_*, z), and correlation functions of diffuse emission ξdd(r, z). We establish a rigorous statistical framework for comparing EWOG against ΛCDM, string theory, loop quantum gravity (LQG), conformal cyclic cosmology (CCC), and celestial holography using Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC), Bayesian evidence, and other model selection tools. The analysis demonstrates that Rubin's ten-year survey can constrain the entanglement contribution parameter Ω⁰ₑₙₜ to within ΔΩ⁰ₑₙₜ < 0.01 at 3σ confidence, potentially providing the first observational tests of quantum-informational spacetime emergence.