De Broglie’s thesis made waves, and in November 1925, Erwin Schrödinger gave a seminar about it in Zurich. When he was finished, Peter Debye said in effect: “You speak about waves, but where is the wave equation?” Schrödinger went on to produce and publish his famous wave equation (Figure 7.4), the master key for so much of modern physics. An equivalent formulation involving tables of numbers called matrices was provided by Max Born, Pasqual Jordan and Werner Heisenberg around the same time. With this new powerful mathematical underpinning, quantum theory made explosive progress.
