# Emergence of the Born rule in quantum optics

Applied Research Laboratories, The University of Texas at Austin, P.O. Box 8029, Austin, TX 78713-8029

### Abstract

The Born rule provides a fundamental connection between theory and observation in quantum mechanics, yet its origin remains a mystery. We consider this problem within the context of quantum optics using only classical physics and the assumption of a quantum electrodynamic vacuum that is real rather than virtual. The connection to observation is made via classical intensity threshold detectors that are used as a simple, deterministic model of photon detection. By following standard experimental conventions of data analysis on discrete detection events, we show that this model is capable of reproducing several observed phenomena thought to be uniquely quantum in nature, thus providing greater elucidation of the quantum-classical boundary.

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### Cited by

[1] Brian R. La Cour and Thomas W. Yudichak, "Classical model of a delayed-choice quantum eraser", Physical Review A 103 6, 062213 (2021).

[2] Brian R. La Cour and Thomas W. Yudichak, "Entanglement and impropriety", Quantum Studies: Mathematics and Foundations 8 3, 307 (2021).

[3] Knud Thomsen, "Timelessness Strictly inside the Quantum Realm", Entropy 23 6, 772 (2021).

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