Dark Matter Phenomenology as Informational Persistence: Nonlocal Gravity, MOND, and the Survival of Curvature Under Coarse-Graining

Observations across astrophysical scales continue to resist a unified explanation within a single ontological framework. Modified Newtonian Dynamics (MOND) accurately reproduces galactic rotation curves but fails in clusters and cosmology, while cold dark matter models succeed on large scales yet struggle to explain galactic regularities without fine tuning. Recent nonlocal gravity models demonstrate that both regimes can be reproduced without introducing new particle species, interpolating between MOND-like behavior in galaxies and dark-matter-like behavior in clusters and cosmology. This work argues that the success of nonlocal gravity is not accidental but diagnostic. It suggests that gravitational curvature responds not only to local mass density, but to information that persists under coarse-graining. Using Living Information Theory (LIT) as an explanatory framework, dark matter phenomenology is reinterpreted as the effective footprint of curvature that cannot be eliminated without violating global informational constraints. From this perspective, dark matter need not be treated as a fundamental substance, but as an emergent description of surviving geometric structure. The paper does not propose a new theory of gravity or reject particle dark matter. Instead, it clarifies why multiple formalisms succeed in different regimes and identifies informational persistence as a missing organizing principle. The framework is explicitly falsifiable and intended as a diagnostic tool for interpreting gravitational phenomena across scales.