Radiatively Stable General Relativity with a Flux-Fixed Cosmological Constant (GCV): A minimal structural statement and empirical falsifier interface

Version note (v1.0.1): Scope clarification only (no new numerics): the radiative‑stability statement is EFT‑level and does not require a global selection/typicality model; selection enters only for distributional predictions of realised ΛeffΛeffΛeff. This record provides a one-page, journal-neutral statement of the Gauged Constant Vacuum-Mode (GCV) framework on its GR-exact branch, together with a minimal, survey-facing falsifier interface. Core claim. GCV realises a GR-exact branch in which the strictly spacetime-constant vacuum mode is gauge-controlled and does not appear as a local gravitational source. Local dynamics remain GR-exact with a flux-fixed integration constant ΛeffΛeffΛeff in the Einstein equations, while the local stress-energy Tμν(loc)Tμν⁽ˡᵒᶜ⁾Tμν(loc) contains only local excitations (matter/radiation perturbations), excluding strictly constant vacuum contributions. Once ΛeffΛeffΛeff is fixed by late-time data, the background expansion on this branch is indistinguishable from flat ΛΛΛCDM (wDE=−1wDE=-1wDE=−1). Scope. This note: states the structural GR-exact claim (constant-mode gauging; ΛeffΛeffΛeff as a flux-fixed integration constant; radiative stability of the strictly constant vacuum contribution within the stated EFT operator inventory), and defines minimal falsifiers designed for late-time observational use (ruler-free geometry and growth-only response tests). This note does not: predict the numerical value or sign of ΛeffΛeffΛeff; provide a UV-unique completion; or claim detection of deviations from GR/ΛΛΛCDM. Numerical constraints and operational likelihood constructions are provided in the cited companion records. Companion records (supplementary modules). See Related works Project homepage: https://johansson.digitalProject overview hub: https://github.com/gcv-framework/gcv-vacuum-energy