This work proposes closure as a universal structural principle within the Elastic Spacetime with Scale-Dependent Coupling (ESSC) framework. Closure is defined as the formation of a relational configuration in which internal relations become mutually consistent and externally stable. Within this framework, stability, observability, and coherence are interpreted as consequences of achieved relational closure, rather than as independent primitives. The paper demonstrates that stable structures across diverse domains—including sensory perception, mathematics, language, and scientific knowledge—can be systematically interpreted as distinct modes of relational closure. Conversely, unresolved problems, inconsistencies, and ambiguities are interpreted as instances of incomplete, excessive, incompatible, or absent closure. A unified classification of both successful and failed modes of closure is introduced, supported by tabular and graphical representations. This allows stability and failure to be described within a single structural framework. A preliminary quantitative measure, the closure fraction f, is introduced to represent the degree of relational completion. This provides a bridge between the structural interpretation developed here and the statistical characterization of closure presented in ESSC v16. The work also connects closure to major physical theories, interpreting quantum mechanics as open relational structure, gauge theories as mechanisms of closure formation, Yang–Mills theory as structured closure, and general relativity as geometric closure. ESSC v18 does not introduce new physical entities or modify existing dynamics. Instead, it provides a structural perspective that unifies stability, observability, and meaning across physical, perceptual, and conceptual domains. This work extends previous ESSC versions:- ESSC v16: statistical realization of closure- ESSC v17: structural origin of closure- ESSC v18: unified cross-domain interpretation of closure The framework suggests that scientific inquiry itself can be understood as a process of identifying and refining closure conditions.
umimoto (Wed,) studied this question.