Quantum mechanics is formulated

In the summer of 1925, the 23-year-old Werner Heisenberg, recovering from hay fever on the island of Helgoland, worked out the mathematics of matrix mechanics, a new way to describe the behaviour of atoms, with Max Born and Pascual Jordan. In 1926 Erwin Schrodinger published his wave equation, which turned out to be equivalent, and in 1927 Heisenberg's uncertainty principle showed that position and momentum cannot both be known exactly. Debates between Niels Bohr and Albert Einstein followed, over the meaning of the theory. Quantum mechanics explains atoms, chemistry and solids, and led to the transistor, laser and computer.

Open on the timeline