We show that the 2025 Nobel Prize experiment, originally conceived within the framework of macroscopic quantum tunneling in superconducting circuits, constitutes an independent experimental realization of the marginal tunneling mode predicted by the quartic Ψ–Γ variational functional.No parameter fitting, external constants, or phenomenological adjustments are used: the observed macroscopic tunneling behaviour corresponds exactly to the unique marginal eigenmode selected by the decision operator Ω under the Z3-irreducible Hessian structure.The Nobel system realizes one branch of the triplet degeneracy, demonstrating that the Ψ–Γ framework predicts, from first principles, the emergence of a single coherent macroscopic tunneling mode with no free parameters.This establishes the 2025 experiment as the first large-scale, independently designed physical verification of the universal spectral mechanism underlying the Ψ–Γ functional.
Livolsi Edoardo (2026) studied this question.