Theoretical Feasibility of Resonant Metric Engineering via Nuclear-Electronic Coupling in the Superheavy Regime

We outline a theoretical framework and validation roadmap for “Metric Engineering”---the controlled modification of a macroscopic gravitational source and the resulting spacetime geometry. The program is organized in three logically distinct layers: (i) standard or algebraic structure, (ii) conditional effective-source and open-system models, and (iii) the superheavy nuclear-electronic research hypothesis. The superheavy regime near Z ≈ 115 is selected as the initial search domain because relativistic electronic contraction and finite-nuclear-size effects produce unusually strong electronic probability density inside the nuclear volume. Spatial overlap is not identified with a new coupling. The central microscopic question is whether a physically admissible interaction operator, selected by the Hamiltonian and environment, can convert nuclear-scale excitation into a coherently retained C-even effective-source response. Constraint Physical Computing (CPC) provides the reference cross-scale integration and validation architecture. The underlying atomic, nuclear, open-system, effective-source, and gravitational calculations remain independently executable with domain-specific methods; CPC is not a prerequisite for those simulations. It supplies the common constraint structure, cross-scale rejection logic, and inverse-design orchestration. The CPC integration layer is organized as five computational gates: Microscopic state → interaction → coherent dynamics → effective source → metric utility. The full research roadmap adds a separate spectroscopic experimental gate before metric inverse design, yielding six program-level decision gates. Failure at any applicable gate terminates the downstream claim. Success at an early gate does not imply propulsion.