Relativitaetstheorie: 1911-1914: Entwurftheorie
Einstein had to resort to a thought experiment to conceive that gravity would no longer be perceptible in a free falling elevator. In the Drop Tower of the Center of Applied Space Technology and Microgravity at the University of Bremen, one can perform and test that experiment in reality. Scientists exploit the weightlessness that occurs when bodies are free falling, for experiments. That way the weightlessness in space is simulated on Earth.