Quantum Forensics: Inferring Photon States via Environmental Bow Waves

This conceptual paper introduces a framework for indirectly inferring the state of photons that remain unobserved, by analyzing their environmental perturbations — here termed bow waves and wakes. Extending principles from quantum state tomography and environment-assisted measurement, this approach treats the environment as a forensic record of photon interactions, using purpose-built conceptual tools such as quantum filters and tick sheets. By combining probabilistic inference with structured environmental observables, it may be possible to reconstruct photon number, polarization, frequency, and path without collapsing the photon’s quantum state. This work builds on prior conceptual tools from photon pulse reconstruction (Davidson, 2026; DOI: 10.5281/zenodo.19221581) and extends them toward observing the unobservable in a controlled theoretical framework.