Structural Criterion for Y-Defect Beta Decay in RQGP

We present a structural criterion for beta decay in the RQGP (Refined Quantum GeometricPhysics) framework, identifying the neutron’s Y-axis polarity mismatch — the Y-defect — asthe structural origin of hadronic instability in the threshold decay class. Using a static Kirchhoffnetwork solver applied to hadronic topology graphs, we derive a composite structural pressuremetric and a three-condition structural decay criterion. Within the tested threshold-ejection class, this criterioncorrectly classifies six of six hadronic topologies. We further show that the Z-axis is structurallypassive across all tested Y-axis transitions, that binding energy is the dominant structuralsuppressor of C3 with analytically computable critical values for each composite, and that threestructurally distinct decay classes emerge from the framework without fitting. The frameworkoperates in dimensionless RQGP structural units; all conclusions are independent of physicalunit correspondence and hold for any vacuum routing penalty Λvac ≥ 26. A structural transitionsequence describing the four-object intermediate state is presented as a topological narrative ofthe decay event.