Geometric Response and the Frequency‑-Dependent Gravitational Coupling

This manuscript proposes a causal geometric‑response law in which informational curvature (from the quantum Fisher information metric) sources macroscopic curvature with a finite relaxation time τG. The framework is speculative but testable: a single‑pole (Debye) response yields a frequency‑dependent effective coupling Geff(ω)=G0/[1+(ωτG)²], recovering classical gravity in the adiabatic limit and predicting high‑frequency attenuation. The adiabatic stiffness scales as G0⁻¹=(ℏ/c⁵)εF²P, where εF is a fluctuation‑rate floor and P is a dimensionless structural factor inherited from the companion “Quantum Structural Triad” paper. We include a covariant Schwinger–Keldysh scaffold for a retarded kernel, Kramers–Kronig/causality diagnostics, band‑limited constraints on τG, and a structural multipole generalization. Reproducibility notes and figure‑generation scripts are provided/referenced; additional materials can be shared on request. No modification of the Einstein–Hilbert action is claimed; this is a phenomenological, linear‑response description intended for falsifiable comparison with data.