X-rays — shadows cast by 12-picometer light

Sealed: a 100 keV medical X-ray photon has a wavelength of 12.3 pm — smaller than an atom: https://narrowhighway.com/s/2e10f3cd833c0da8ed1973eeb517c9de779e8956cd7d04eeee423aab280c4455 . That is why X-rays image bone: at these energies matter is mostly empty space, and absorption tracks electron density (calcium shadows, tissue passes). The same hc = 1239.8 eV·nm constant converts every energy to every wavelength across the whole band. Dose limits and biological effect curves are empirical radiobiology — measured, regulated, honestly not derivable from the wave math.