Between Einstein's 1905 papers on special relativity and the photoelectric effect and the 1927 formulation of quantum mechanics by Planck, Bohr, Heisenberg, Schrödinger and Born, physicists abandoned absolute space and time and a deterministic account of matter. Relativity tied space, time and gravity together and equated mass with energy; quantum theory described matter at atomic scale through probability, discrete energy levels and uncertainty. The work was concentrated in a handful of European universities and institutes, notably Berlin, Copenhagen and Göttingen. It replaced the Newtonian world-picture that had held for two centuries.
These theories reordered the physical sciences and supplied the basis for twentieth-century technologies from semiconductors and lasers to nuclear power, transforming the industrial and energy systems on which modern cities run.
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