Abstract

The mathematical formalism of quantum theory has been known for almost a century, but its physical foundation has remained elusive. In recent decades, many physicists have noted connections between quantum theory and information theory. In this study, we present a physical account of the derivation of quantum theory's mathematical formalism based on information considerations in physical systems. We postulate that quantum systems are physical systems with only one independent adjustable variable. Using this physical postulate along with the conservation of the total probability, we derive the standard Hilbert space formalism of quantum theory, including the Born probability rule. Our complete derivation of quantum theory provides a clear and concise physical foundation for the mathematical formalism of quantum mechanics.