Asymptotic SafetyRG Flow as Nucleus in Lean 4
Astrid Eichhorn's asymptotic-safety program is formalized here as a constructive proof pipeline: linearized beta flow, UV projection, nucleus structure on coupling regions, calibrated phenomenology, tensor-balance witnesses, and executable RK4 extraction. The central move is algebraic, not rhetorical: the RG restriction is implemented as a genuine nucleus on UV-safe regions.
| Paper Theme | Lean Surface | Status |
|---|---|---|
| UV fixed point and truncation data | CouplingSpace + BetaFunctions | PROVED |
| RG projection and UV admissibility | RGFlow | PROVED |
| Nucleus structure on coupling regions | NucleusInstance | PROVED |
| Matter lifts and calibrated phenomenology | MatterSector + GravityMatter + Predictions | PROVED |
| Scale-dependent ratchet | ScaleSymmetry | PROVED |
| Tensor screening / antiscreening balance | TensorFieldTheory/* | PROVED |
| Executable extraction sanity | Extraction/* + Sanity | PROVED |
The linearized benchmark flow vanishes exactly at the gravitational fixed point.
Screening plus nonnegative portal coupling forces nonpositive portal flow.
UV projection is a genuine idempotent restriction map.
The simplest portal coupling is removed on the screened UV-safe locus.
The RG restriction becomes a genuine nucleus on coupling regions.
Constructive exclusion is internalized as Heyting negation on the UV-safe carrier.
Matter content contributes a positive backreaction when the constituent lifts are positive.
Prediction bands are derived from separate calibration and RG-drift budgets.
The neutrino theorem uses model-side damping and backreaction rather than restating its conclusion.
Coarser scales yield smaller admissible regions.
The scale-indexed admissible sets package into a dimensional ratchet.
The tensor quartic witness is derived through the screening/antiscreening balance mechanism.
Hover over the nodes to trace the proof spine from coupling-space definitions to the top-level prediction, extraction, and regression layers.
Nine couplings, including the portal coordinate.
gravitationalFixedPoint_portalOff — The benchmark fixed point already lives on the portal-off slice.
Lean Proof Artifacts
Verified C Artifacts
Safe Rust Artifacts
Eichhorn, Held, Donà, Shaposhnikov/Wetterich, tensor-balance sources
Nucleus instance, constructive negation, calibrated prediction layer
Faithful C and Rust computational mirrors of the flow surface
Content-addressed archives for paper, proof, and code surfaces
Formal Verification Certificate
The asymptotic-safety slice has been rechecked as a standalone Lean package and exported with matching C and Rust mirrors. The central nucleus claim and the downstream prediction/exclusion theorems are bounded to what the kernel and the extracted artifacts actually verify.
Asymptotic Safety • Lean 4 + Mathlib • Apoth3osis Labs
