Bohr’s electron orbits produced some correct spectra but no experiment watched an electron complete one. During a bout of hay fever on Helgoland, Werner Heisenberg reorganized the problem around measurable transition frequencies and intensities.
The strange multiplication rules in his calculations were recognized by Max Born as matrix mathematics. Matrix mechanics worked without assigning electrons hidden classical paths.
This is not merely poor equipment disturbing an otherwise exact trajectory. A state tightly localized in position necessarily contains a wider spread of momentum.
The bold move was methodological. When the inherited picture stopped producing consistent predictions, Heisenberg did not decorate it. He removed the orbit and let relations among observations carry the theory.
