To “see” these things at smaller and smaller distances, we needed touse beams of particles with
smaller and smaller wavelength, and hence, higher energy.
2.4 Atomic Spectra*.
Hydrogen was ultimately the true test of the quantum theory. Very high accuracy measurements were
made using diffraction gratings. These were well understood in non-relativistic QM and understood
even better in the fully relativistic Quantum Field Theory, Quantum Electrodynamics.
The figure below show theenergy levels in Hydrogen, thetransitionsbetween energy levels,
and the wavelength of light produced in the transition. TheLyman seriescovers transitions to