Structural Decoherence in Fundamental Physics_ Why String Theory Cannot Converge to Proof

Abstract This paper conducts a structural audit of string theory considered as a research program. It introduces no new physics, proposes no alternative theory of unification, and does not argue that string theory is false. Instead, it asks a prior and more basic question: whether string theory admits convergence toward proof or disproof in principle under any physically realizable epistemic process. Using only internal features of the program—its hypothesis space, degrees of freedom, and the mapping between empirical evidence and theoretical realization—the paper analyzes whether accumulation of work can induce epistemic contraction. It is shown that string theory generates an effectively unbounded landscape of inequivalent vacua, that empirical data maps non-injectively onto this space, and that refinement expands rather than reduces admissible models. As a result, no elimination mechanism or monotonic progress metric exists. The paper classifies this condition as structural decoherence: a failure of convergence that is not empirical, technical, or provisional, but intrinsic to the framework’s generative structure. Under these conditions, string theory cannot function as a candidate physical theory admitting proof. Reclassification as a mathematical framework avoids falsification only by abandoning physical truth claims. The conclusion is therefore not rejection, but structural reclassification.