Record–Constraint Resolution of the Screen Problem
Sergiu Margan
We address the screen problem—why a spatially delocalized quantum input interacting with a macroscopic detector yields a single localized, persistent dot on each trial. The approach is record-first: a dot is treated as an operationally certified record, stable, redundantly witnessed, and readable, and the measurement problem is reformulated as the problem of when such records become single-valued facts. To avoid semantic collapse, subsystem structure is grounded in locality via a net of local observable algebras rather than an assumed Hilbert-space tensor factorization. The paper then introduces an exact notion of certification in algebraic terms: distinct outcomes are exactly certified when they induce disjoint GNS representations of the quasi-local algebra, as can occur through outcome-dependent infrared or asymptotic dressing. In that regime, a Record Superselection Axiom (RSA) follows as a sector constraint on physically admissible quasi-local observables, excluding cross-sector interference measurements after certification. This yields a no-smear lemma for single events, supports the canonical Born weights on consistent record-history families, and implies a Wigner–Friend recoherence no-go past exact certification. Finally, the paper proposes an in-principle discriminator: in a complete witness-capture unmeasurement protocol, unitary-only accounts predict recoverable interference as capture and control approach unity, whereas exact sector disjointness predicts a principled obstruction once outcomes enter disjoint sectors. The result is a bounded, testable framework linking records, locality, and admissibility in a concrete resolution of the screen problem.
•Mar 28, 2026•0 citations