A gapped ground state of a quantum spin system has a natural length scale set by the gap. This length scale governs the decay of correlations. A common intuition is that this length scale also controls the spatial relaxation towards the ground state away from impurities or boundaries. https://www.alarecre.com/Wizarding-World-Harry-Potter-Scar-and-Glasses-iPhone-13-Pro-MagSafe-Case-p90262/