HERA, LOFAR, SKA-low, and eventually DARE can test these predictions.
2. Cosmic Shear Lensing
Relevance:
 Weak gravitational lensing, or cosmic shear, probes the integrated mass distribution along the line of sight, sensitive to both geometry and growth history.
Predictions:
Fractal density leads to intermittent over/underdense structures, modifying the lensing power spectrum at intermediate-to-small angular scales.
Layer boundaries induce non-Gaussian lensing kernels and angular scale decoherence in lensing B-modes.
Apparent violations of the Limber approximation at certain redshift intervals due to nonlocal correlations across layers.
Instruments:
Euclid, LSST, Roman Space Telescope will be instrumental in extracting high-resolution shear maps.
3. Phase-Correlated Gravitational Wave Backgrounds
Relevance:
 The stochastic gravitational wave background (SGWB) captures cumulative signals from early-universe processes, including inflation, phase transitions, and topological defects.
Predictions:
Layer transitions produce phase-echoed signatures in the SGWB, potentially detectable as correlated oscillatory modulations.
Fractal geometry causes spectral deviations from a pure power-law SGWB and introduces angular anisotropies in the background.
The geodesic scattering of GWs across layered vacua could manifest as temporal lensing or spectral ringing in observed GW events.
Instruments:
LISA, DECIGO, Einstein Telescope, and future pulsar timing arrays (PTAs) like SKA-PTA are suited for such probes.
Summary of Future Prospects:
These future directions not only hold the potential to validate or falsify our framework, but also to redefine cosmological inference by exposing the deep interplay between topology, information, and quantum structure of spacetime. The observational path forward is rich and multidisciplinary, spanning radio astronomy, gravitational wave physics, and precision cosmology.
Appendix A: Full Derivation of Interference-Modified Friedmann Equations
