A Relational Coherence Account of the Double-Slit, Delayed-Choice, and Quantum Eraser Experiments: Global Loop Closure without Retrocausal Signaling

We present a full relational-coherence reformulation of the double-slit family of experiments—including which-path, delayed-choice, and quantum-eraser variants—within the NullLink Relational Coherence Framework (RCF). In this approach, photons are not particles traversing spacetime trajectories; rather, they instantiate bundles of potential null relations between event-nodes in a discrete causal network. The presence or absence of interference is governed by the survival or suppression of cross-branch relational compatibility under environmental tagging. Central to this formulation is the coherence overlap functional χ, which quantifies whether
two alternative transport channels remain admissible members of a common loop-closure class at a given coherence depth—our operational proxy for time. In this view, wavefunction “collapse” is reinterpreted as global consistency selection at loop closure: only those relational histories satisfying all boundary constraints (detector records, environmental couplings, delayed measurements) stabilize into realized events. We prove a Global Consistency Theorem demonstrating that delayed-choice configura
tions do not require backward-in-time causal influence. Instead, apparent retrocausality arises as post-selection across relationally admissible histories evaluated at the depth where closure occurs. From the overlap functional, we derive expressions for interference visibility, partial which-path suppression, and conditioned subensemble fringes in quantum-eraser geometries. Toy lattice simulations confirm the analytic results and reveal experimentally testable asymmetries: (i) structured decoherence gradients induce fringe centroid drift; (ii) late erasure restores interference conditioned on compatibility amplitude—not merely Hilbert overlap; and (iii) hierarchical multi-slit arrays exhibit selective loop dominance via tension minimization. These results embed canonical quantum optics phenomena within a broader coherence–decoherence
 ontology that also unifies gravity, the emergence of time, and biological information integration as developed in related work.