CHAINSTATE-X: Transmedium Photonic Optimization Substrate

CHAINSTATE-X is a programmable heterogeneous physical substrate that maps CHAINSTATE energy landscapes onto optical, optoelectronic, phononic, thermodynamic, and—experimentally—QED-boundary degrees of freedom under a common RISC-V executive and a common CS.PHYSOPT instruction-set architecture. The paper defines a seven-layer architecture, an energy-landscape intermediate representation, a substrate-neutral runtime with classical CMOS fallback on every path, and a two-gate execution model that separates pre-execution authorization (EXEC_AUTH) from post-verification retirement. The device family spans a commercially manufacturable core—a RISC-V executive with a photonic tensor engine, a photonic Ising engine, a photonic reservoir, and a memristive persistent-state layer, targeting process kits at AIM Photonics, imec, LioniX, IHP, and Fraunhofer HHI—and a research-grade frontier comprising a diamond phononic-crystal substrate and three independent laboratory configurations for Casimir cavity, dynamic Casimir effect, and sonoluminescence experiments. Constitutional guarantees inherited from Paper XVII (V1 - V9 vetoes, SENTINEL five-gate pipeline, ALLOW gate, egress filter Γ) are enforced in hardware across every substrate, and every substrate has a specified falsification threshold. Performance figures use an E/A/T evidence taxonomy: E for experimentally demonstrated on CHAINSTATE-X hardware, A for literature anchor from a cited external experiment, T for CHAINSTATE-X target or specification not yet demonstrated.