The Condensation-Collapse: Redefining Quantum State Reduction through the PDA Inequality

The measurement problem in quantum mechanics—how and why a superposition collapses to a definite state upon measurement—remains a central puzzle. Here, we propose a physical redefinition of wave function collapse as a process of information condensation, governed by the fundamental inequality ΔSth≥kB⋅∣ΔSent(S)∣ΔSth≥kB⋅∣ΔSent(S)∣ (the PDA inequality). We show that collapse is not a loss of information, but a transfer from local superposition to non-local system-environment correlations, necessarily accompanied by thermodynamic entropy production. This approach preserves unitarity, explains the origin of irreversibility, and offers a testable alternative to existing interpretations.