Entanglement, EPR, and Spatial Mediation: A Three-Layer Framework with a Communication-Cost Diagnostic

This paper revisits Einstein's "spooky action at a distance" by isolating a specific source of the EPR puzzle: the tacit assumption that every physically relevant relation between distant systems must be mediated by signal-like propagation through background space. A three-layer framework is developed: Layer I (Operational): Entangled correlations need not be explained by ordinary spatial propagation. A spatial mediation cost C_SM is introduced — the minimum average classical communication in measurement-independent post-input simulation models. In the CHSH no-signalling sector: C_SM = max{0, B_CHSH/2 − 1}. Tsirelson-saturating correlations impose a tax of √2 − 1 ≈ 0.414 bits/run. Layer II (Structural): Patterns of entanglement may encode or reconstruct effective geometry, illustrated by toy mutual-information reconstructions on lattice vacuum states. Layer III (Dual): In special gravitational settings, some entangled states may admit geometric dual descriptions (ER=EPR, holography). Applied to the two-qubit Werner family, the diagnostic cleanly separates entanglement (v > 1/3) from CHSH-certified operational non-spatiality (v > 1/√2). 13 pages, 1 figure.