IMM Paper 3: Lorentzian Signature as the Stable Informational Valley

Under IMM spectral contraction with Δ(x)≥Δ_min>0, non-Lorentzian metric deformations decay as exp(-∫Δdℓ'). Lorentzian signature is a stable fixed point of the coarse-graining flow (Proposition). The uniqueness step requires FRG fixed-point classification (open gap, concrete pathway provided). Comparison with asymptotic safety, causal sets, Connes geometry, CDT.