Essential Theoretical Demarcation between Empirical Constant π and Cosmic Intrinsic Constant π₁ --Establishment of Universal Rigid Scale Standards under the PFUS Theoretical Framework

Within conventional mathematics, the circumference constant π has long been universally recognized as a fundamental constant applicable across the cosmic domain. Nevertheless, traditional π originates from artificially constructed three-dimensional flat idealized models and belongs to a low-dimensional empirical superficial constant with inherent theoretical limitations. Inheriting the core axiomatic achievements of zero-coupling interfaces and adhering to the Phase-Fusion Universal Structure (PFUS), this paper dissects the origins and limitations of traditional π, rigorously classifies empirical constants and cosmic intrinsic primordial constants, and logically derives the universal cosmic intrinsic rigid scale constant π₁=12/11 based on the eleven-dimensional topological architecture and single-layer universal topological closure. This study verifies the objectivity and universal applicability of π₁ and consolidates the core scale foundation of the entire PFUS system.