Niels Bohr: Life Behind the Physics

Niels Bohr, with his model of the atom, led physics into the quantum era. In the last of this season's Perimeter Institute public lectures, his grandson Vilhelm will talk about personality and his influences

Even though we know better, many physicists still picture the atom as a mini solar-system type of affair, with tiny electrons orbiting a heavy nucleus. This is the picture that emerged from Rutherford's scattering experiments (ruling out a stodgy pudding of an atom with electrons embedded like raisins throughout, for instance).

One problem with this 'orbiting electrons' idea is that classical electromagnetism predicts that the electrons should lose energy and spiral into the middle very quickly. This would mean all atoms would be catastrophically unstable, in serious violation of observational evidence.