Improved Information-Coupled Scalar-Tensor Theory (i-ICST v9): Holographic MOND Scale, Symmetron Screening, and Cosmological Predictions

This work presents version 9 (v9) of the Improved Information-Coupled Space-Time (i-ICST) theoretical framework, a scalar-tensor cosmological model aimed at unifying MOND phenomenology and dark energy within a consistent relativistic structure. In this updated version, several key improvements and corrections are introduced. First, the MOND acceleration scale is derived holographically asa₀ = (cH₀ / 2π) √ (ΩDE (1 − w₀) ), providing a cosmological origin for the acceleration scale, although a residual discrepancy (~18. 8%) with SPARC observational data remains unresolved. Second, the screening mechanism is implemented using a Symmetron approach, yielding a density-dependent coupling that restores General Relativity on cosmological scales while activating MOND-like behavior in low-density galactic environments. Third, the interpolation function is corrected to ensure consistency with the observed radial acceleration relation (RAR), recovering the expected deep-MOND scaling behavior. The model is tested against multiple datasets, including SPARC galaxy rotation curves, DESI BAO, Pantheon+ supernovae, and Planck CMB priors. It achieves competitive agreement with ΛCDM while reducing the S₈ tension to ~1. 9σ. A key prediction of the model is the redshift evolution of the MOND acceleration scale, a₀ (z), which increases with cosmic expansion. This effect is potentially testable using high-redshift galaxy rotation curves from JWST observations. Despite these advances, several open problems remain, including the need for a full Boltzmann CMB analysis, the unresolved discrepancy in the MOND scale, and consistency of the dark energy equation of state. This version represents a significant step toward a testable alternative to ΛCDM and is intended for further theoretical development and observational verification.