(GQR30) Measurement as Gating: A Geometry-First Review of the Double-Slit and Quantum Eraser Experiments.

The double-slit experiment and its quantum eraser variants remain central to discussionsof quantum measurement, interference, and which-path distinguishability. Despite the long-standing experimental clarity of these systems, their interpretation is often presented in observer-dependent or information-theoretic terms, leading to persistent conceptual confusion.In this review, we re-examine the double-slit and quantum eraser experiments using ageometry-first perspective in which measurement is treated as a structural process rather thanan epistemic one. Specifically, we frame a measurement event as the opening of a condensa-tion gate that permits an otherwise distributed quantum process to localise irreversibly intoa stable record. Interference persists while no exclusive gate is available; which-path markingintroduces distinct gated exits; and quantum erasure corresponds to the removal of geometricdistinguishability, without invoking retrocausality or observer privilege.This reframing preserves all established experimental results while avoiding collapse postu-lates and knowledge-based interpretations. By emphasising constraint, admissible structure, andirreversible localisation, it offers a mechanistically neutral language for understanding quantumerasure experiments and situates them within a broader class of geometry-conditioned dynamicalsystems. Full 70 article programme https://github.com/jamessutton600613-png/GQR/blob/main/Programme_Index.md The programme contains both standalone and self referencing articles. These can all be read as notes in proof of GQR1.