UED Reconstruction Programme — Paper 4: Detection, Photon Events, and Quantized Manifestation

Paper 4 of the UED Reconstruction Programme reconstructs discrete optical detection without assuming that optical propagation must consist of travelling particles. It begins from the continuous source-field-receiver architecture established in Paper 3 and asks what additional source or receiver conditions are required for an optical consequence to become a countable event. A photon event is defined operationally as a discrete resolved optical consequence at a source or receiver boundary. The empirically calibrated event-energy relation is retained asεγ=hν\varepsilon_\gamma=h\nu,while hh is treated at this stage as the measured action-scale conversion between resolved frequency and boundary-event energy rather than as a quantity already derived microscopically from SVE. For a calibrated narrowband receiver, the signal-event hazard isλs=ηBPB/(hν)\lambda_s=\eta_B P_B/(h\nu),with independently measurable receiver efficiency, optical power, dark-event rate, dead time, and timing response. The framework reproduces low-flux linear count rate, Poisson statistics under independent stationary conditions, photoelectric thresholds, detector saturation, dark-count backgrounds, discrete interference sampling, and polarization-dependent event rates. The principal structural result is the Quantized Manifestation Proposition: discrete registered energy exchange with event scale hνh\nu can coexist mathematically with continuous intermediate optical transfer. Discrete detection therefore does not, by itself, establish discrete propagation. The paper also separates propagation delay, Alignment Threshold Time (ATT), detector amplification latency, mean event waiting time, dead time, and electronic timestamp delay. It does not claim that all optical discreteness originates at the receiver and leaves the microscopic origin of hh, receiver thresholds, and matter-based event structure explicitly open for subsequent papers.