LESE-NuclearQA: Physics-Derived Structural Coherence Indicator Applied to US PWR Inspection Data

We apply the LESE (Lattice Entropic Structural Engine) framework to publicly available NRC inspectionfindings from three independent US pressurised water reactors. The Wᵢj node mapping is derived from NRCSignificance Determination Process methodology (IMC 0609) and defined prior to examining outcome data. The structural coherence index Wₘin = minWᵢj is compared against the universal fragility threshold W* =en¹ = 0. 36788, derived analytically from the fixed point of the entropic flow equation dW/dt = k (1 + log W) and not calibrated on any nuclear dataset. Results: Wₘin crossed W* approximately 8 months before theDavis-Besse RPV head cavity discovery (2002), 12 months before the Crystal River 3 containmentdelamination (2009), and 12 months before the San Onofre steam generator tube wear event (2012). Thesame unmodified Wᵢj mapping was applied to all three plants. Combined: N=4 RED events across 3independent plants, TPR=100%, three different failure mechanisms, two different PWR vendors, threedifferent operators. A VVUQ validation roadmap toward formal qualification is included