Relational Separation Does Not Erase Registration: Persistent History, Distance Formation, and the Entanglement Application in Registration Theory

This paper develops the Registration Theory (RT) account of relational separation, persistent registration history, and measurement, and applies it to entanglement. It argues that increasing host-resolved spatial separation does not by itself constitute an erasure operation on a previously established consequential registration. Within RT, metric distance is downstream of persistent relational separation and therefore cannot by itself be assumed to terminate the registration history from which that separation developed. The paper introduces a Common Registration-Origin Class through an augmented registration-space construction that distinguishes host-resolved spatial separation from the underlying registration relation. This provides a formal framework in which registrations may become widely separated in reconstructed spatial geometry while retaining a common registration history. A central result of this version is a refinement of the RT concept of measurement. Measurement is not introduced as an additional primitive operation acting upon an already existing physical state. Instead, measurement is defined as the host-distinguishable manifestation of a consequential Trinity relation. Trinity supplies the mutually related space-, time-, and energy-facing manifestations; the Irreducible Rule of Distinction (IRD) makes relational differences physically distinguishable; registration makes those distinctions consequential and capable of persistence. Accordingly, a mutual registration event is resolved through its distinguishable Trinity relation. Ratio descriptions such as [S:T:E] and the corresponding reference charts express host-relative comparisons rather than independent ontological components. The paper replaces an unnecessarily strong common-scale-blindness assumption with relational co-scaling: simultaneous scaling of a registration and its comparison reference leaves the corresponding ratios invariant without requiring absolute Trinity scale to be physically irrelevant. This result also provides a direct follow-up to the preregistered opposition-to-incorporation problem frozen in “From Opposed Expansion to Persistent Registration” (October 1, 2026; DOI 10.6084/m9.figshare.34050480). The previously unspecified host-resolved event E_n is identified with the distinguishable Trinity manifestation of the consequential mutual registration. For the existing reduced incorporation law A_{n+1}=(1-eta_n)A_n+eta_n E_n, the realized incorporation fraction can consequently be reconstructed from the event-relative contraction. The paper does not claim completion of the preregistered angular-threshold reconstruction. The remaining forward problem is to derive from RT dynamics how retained registration history together with the present boundary, opposition, and phase structure determines the successor registration and hence the incorporation rate eta_n and eventual entry into the persistent-closure class. The preregistered prohibition against angle-dependent calibration, changing closure criteria, or post-hoc parameter fitting therefore remains in force. For entanglement, the paper proposes that spatial separation need not erase a persistent bilateral registration established through a common history. This supplies an RT interpretation of entanglement as persistent relational organization but does not claim a derivation of Bell/singlet correlations. Deriving the corresponding joint measurement statistics remains a separate theorem obligation.