Complete Spacetime Quantum Information Theory:Mathematical Framework and Multi-Scale Empirical Validation

This paper proposes and systematically elaborates a complete physical theory framework based on quantum information first principles—the Complete Spacetime Quantum Information Theory (CSQIT). The theory is founded on three core axioms: Information Ontology, Holographic Duality Principle, and Self-Referential Dynamics Principle. From these axioms, we derive a self-consistent system of mathematical equations, including the Self-Referential Evolution Master Equation and the Modified Holographic Constraint Equation. The theory naturally incorporates quantum information measures such as information integration C and topological order Q as fundamental dynamical variables, whose expectation values modify the spacetime geometry relationship dominated by entanglement entropy. From first principles, we prove the modified Einstein field equations and the conservation of the information energy-momentum tensor. By defining inter-scale coupling constant recurrence relations, the theory achieves precise quantitative validation across five disparate scales—atomic, molecular, condensed matter, states of matter, and cosmology—with predictions showing remarkable agreement with experimental data (e.g., R2 > 0:95 for covalent radii of 86 elements, 99.9% accuracy in predicting the cosmological constant ). The theory also provides an emergent internal model for observers and measurement processes, and makes novel testable predictions for molecular reaction rates, topological material behavior, and cosmological constant evolution.