The physicist and scientific theorist Thomas S. Kuhn presents a new theory about the development of science in his work The Structure of Scientific Revolutions. The history of science is not the progression of the accumulation of knowledge, but is marked by deep disruptions, so-called paradigm shifts. A paradigm is a basic consensus about central theories, perceptions and research problems shared by scientists in the same fields and under which conditions they do their day-to-day work – ‘normal science’. When unexpected results come to light, anomalies that cannot be made to fit into prevailing theories, the paradigm falls into crisis. After a phase of fundamental scientific controversy the “extraordinary science” establishes a new paradigm. To Kuhn, the replacement of classical physics with modern physics represents just such a paradigm shift.