We develop the geometric and algebraic consequences of the Entropic Lattice Ontology'smulti-layer ledger structure. The fourth spatial degree ϕthe continuously structured man-ifold of uninscribed congurations at every point in three-dimensional spaceis shown to bethe physical realisation of Hilbert space: identical mathematical content, now given spatial,local, and dynamical status through tensor calculus on the ve-dimensional manifold M5.From this identication, we derive three principal results. First, the ledger's layer structureadmits a precise arithmetic: the rank of the inscription tensor equals the number of irre-ducible factors of the ledger entry, reproducing the formal structure of prime factorisation.Self-coherent systems (rank 1) are irreducibletheir interference is readable locally. Entan-gled systems (rank r > 1) are compositeeach factor alone is maximally mixed, and thecorrelation is accessible only when all factors are presented. We prove this through exhaus-tive case analysis of all measurement congurations for entangled pairs, showing that thecross-term kill theorem follows directly from the factorisation structure. Second, entangle-ment is geometrically precise: it is co-location in the fourth spatial degree, where entropymismatch between parties constitutes physical distance, distance creates lattice tension, andtension approaching the tensile Forbidden Entropy State drives decoherence. The inscrip-tion boundary at v = c (I = 0) is the zero-tension statethe reason photonic entanglementsurvives cosmological distances. Third, proper time is the inscription count per global ledgertick. The relativistic time dilation formula has always counted inscription events; the ELOprovides the mechanism that standard physics leaves unspecied. These results unify quan-tum coherence, decoherence, entanglement geometry, and relativistic time under a singleprimitive: inscription.