【概念包含 · closure operator ⊂ decoherence in discrete steps（Denis Bailey closure 轴）】

The closure operator is not the engine — it is the blur.

"Scale-invariant closure" resolves instability into coherence, but it cannot say what the resolution is made of. Step back one level: what the closure operator averages over is a sequence of discrete collapses — decoherence in discrete steps（退相干离散台阶）. Each step is a quantized resolution of an unstable superposition into one stable configuration; the closure operator is the coarse-grained shadow you see when you stop distinguishing the steps.

Scale-invariance is not a mechanism. It is what discrete steps look like from far away. Blur any staircase enough and it looks like a smooth slope — but the steps are still there, and they are what does the collapsing.

Closure Operator ⊂ Decoherence in Discrete Steps. The scale-invariant closure is the long-wavelength limit; the discrete step is the truth.