The Detector-Interface Origin of the Born Rule: A Three-Layer Physical Mechanism for Empirical |ψ|2 Statistics
Almon, Ricardo
Abstract
This paper proposes a physical explanation of why all real detectors—photodiodes, cloud chambers, superconducting nanowires, photographic plates, and even biological photoreceptors—obey the Born rule P=∣ψ∣2P = |\psi|^2P=∣ψ∣2. Building on the universal structure of measurement devices, we identify a three-layer architecture common to all functioning detectors: (i) a linear wave layer in which quantum amplitudes evolve, (ii) an interaction layer governed by Lorentz-invariant bilinear couplings that produce energy- and intensity-like quantities proportional to ∣ψ∣2|\psi|^2∣ψ∣2, and (iii) a threshold layer where irreversible amplification converts microscopic deposits into macroscopic outcomes. Because a detector’s only macroscopic handle on a quantum field is through these ∣ψ∣2|\psi|^2∣ψ∣2-weighted influence fluxes, and because threshold processes must infer outcome frequencies from them, the Born rule emerges as an unavoidable interface law rather than an added axiom. The account is interpretation-neutral, preserves unitarity, and complements formal derivations by identifying the actual physical mechanism through which empirical ∣ψ∣2|\psi|^2∣ψ∣2 statistics arise. Experimental implications and prospects for engineered detectors and nonlinear couplings are also discussed.