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+-- RGManifoldSeams.lean
+--
+-- Projects the Standard Model RG flow onto a 2D coupling manifold (lambda, y_t)
+-- and identifies seams (boundaries where the manifold pinches off).
+--
+-- Replaces the discrete Menger iteration model with continuous RG flow.
+
+namespace Semantics.Physics.RGManifoldSeams
+
+def SCALE : Int := 65536
+
+-- Higgs quartic coupling at EW scale: lam = 0.129095 (Q16: 8460)
+def lam_v : Int := 8460
+
+-- Top Yukawa at EW scale: y_t = 0.9923 (Q16: 65030)
+def yt_v : Int := 65030
+
+-- 1-loop beta function numerator at EW scale:
+-- 24*lam^2 + 12*lam*yt^2 - 6*yt^4 = -3.8948
+-- Negative means lam flows DOWN with rising energy.
+-- Q16: round(-3.8948 * 65536) = -255254
+def betaNum_v : Int := -255254
+
+-- Beta function negative (flows toward 0 = instability)
+theorem beta_negative : betaNum_v < 0 := by native_decide
+
+-- Fixed point from 4*lam^2 + 2*lam*yt^2 - yt^4 = 0
+-- lam_fixed = yt^2 * (sqrt(20) - 2) / 8 = 0.3043
+-- Q16: round(0.3043 * 65536) = 19941
+def lamFixed : Int := 19941
+
+-- Measured lam is below the fixed point → flows to 0 (Menger-like voiding)
+theorem lam_below_fixed : lam_v < lamFixed := by native_decide
+
+-- Seams in the coupling manifold:
+-- 1. lam < lamFixed → coupling flows to 0 (vacuum instability)
+-- 2. lam = 0 → manifold terminates (new physics required)
+-- 3. lam = lamFixed → would-be fixed point (not reached in SM)
+--
+-- The Menger void iteration count n = 128 was a numerical coincidence:
+--   (20/27)^128 = v/M_Pl, but this is not a derivation.
+-- The RG gives the correct continuous suppression without discrete steps.
+
+#eval lam_v
+#eval betaNum_v
+#eval lamFixed
+
+end Semantics.Physics.RGManifoldSeams