(Appendix) Experimental Test of Space Strain Smoothing in HDC Gravity Framework

**Experimental Test of Space Strain Smoothing in HDC Gravity Framework** This paper presents a complete, reproducible experiment to directly test whether gravitational gradients can be actively modified through coherent strain interference – without mass redistribution. **Key Features:** • Strictly falsifiable between GR linear superposition vs. HDC nonlinear strain dynamics • Coaxially modulated tungsten rings (piezo-driven, µHz–1 Hz, phase-stable to 10⁻⁴ rad) • Detects Δg ∼ 10⁻¹²–10⁻⁹ m/s² via superconducting gravimeters or atom interferometers • Full geometric specs, error analysis, and numerical strain simulations included **Scientific Significance:** A positive result would demonstrate that *space itself* possesses a modifiable physical strain state (ε(x)), separating gravitational physics from pure spacetime geometry. The setup tests HDC's core prediction: ∇ε_eff ≠ Σ∇ε_i under coherent conditions. **Reproducibility:** All parameters, geometries, control configurations, and data analysis protocols are explicitly defined. No proprietary technology required. **Related Work:** Builds on HDC formal foundation (DOI:10.5281/zenodo.15782444)[file:2] *Journal-ready theoretical proposal with practical experimental roadmap.*