Causal Structure Cosmology: A Unified Framework of Realizable Structure

We present a cosmological framework in which the universe is described in terms of causal structure rather than independent entities. Within this framework, not all structural configurations are realizable, introducing a constraint that governs the evolution of the system. Observable quantities arise from the accumulation of realizable structures over structural time. For analytical purposes, this constraint can be represented by a function A(E,T), which regulates the contribution of structural configurations to observable dynamics. Under this constrained accumulation, the resulting observables exhibit a single-sign curvature invariant, quantified by the curvature indicator (RCI). This invariant propagates into the statistical domain, producing sign-coherent behavior in the sign-coherence statistic (SCS) and significant Z-values under effective sample size correction. We refer to this framework as the Causal Structure and Structural Model (CSSM). The present formulation establishes a self-consistent linkage between causal structure, realizability constraints, accumulation, and observable signatures, providing a testable alternative perspective to conventional cosmological descriptions.The framework is directly falsifiable through curvature sign behavior and statistical coherence.