On the Elementary Quantum of Energy Transfer in Electromagnetic Radiation: Toward a Unified Description of Radiative Transport

The universality of the speed of light c across the electromagnetic spectrum implies that the mechanism of radiative energy transfer is identical for all frequencies. This universality raises a question that the standard interpretation, in which each photon constitutes a single indivisible transfer event of its own energy, does not address: can transfer events differing by twenty orders of magnitude in energy produce identical kinematics? We propose that all electromagnetic radiation is transported through a fixed elementary quantum E_min = 6.626 × 10⁻³⁴ J, identified empirically as the initial term of the geometric progression of spectral energies. The number of elementary transmission acts associated with radiation of energy E is n_acts = E / E_min. This ratio, computed from independently measured quantities, yields the verified result n_acts = ν across 30 orders of magnitude of frequency, from ELF radio waves at 1 Hz to UHE gamma rays at 2.5 PeV (LHAASO, 2024). Planck's constant h retains its value; its meaning is clarified as the ratio E_min/ν₀, where ν₀ = 1 Hz. A fundamental structural consequence is the identity n_acts × λ = c, universally verified: the speed of light emerges as the total distance covered by elementary transmission acts per second, expressing its universality as a structural property of discrete radiative transport. No new physical constants are introduced. The framework is fully consistent with all established experimental results. This deposit includes the English version (primary) and the Italian version of the same work.