Michelson And Morley's Experiment

Michelson and Morley designed an experiment to test the theory of the aether. It is considered to be the first strong evidence against the theory of the aether. Primarily for this work, Albert Michelson was awarded the Nobel Prize in 1907.

The aether was believed to be a medium in which light could travel. At the time, people knew thoroughly about sound waves and that sound required a medium in which propagate. They took this knowledge of sound waves and thought that the same applied to other waves, including light. Many scientists had created experiments trying to detect the aether, however they all failed, yet others decided that their equipment was not 'sensitive' enough. People had a very strong belief in the aether until about the 1950's. Albert Einstein also showed that the aether was not necessary.

Michelson and Morley used the concept of racing two boats. One would go 2km up a river and back to the starting point while another would go across the river 2km and back. The boat that goes across the river comes back quicker than the boat going up the river, as this boat has to, at first, go against the current. The light rays were to replace the boat and the aether would act as the current. A light detector was placed so that it could detect any variations. They placed the apparatus on a mercury so that it could be rotated around in an attempt to place the light against the aether (the aether was believed to be transparent so they could not see it or feel it).

Michelson and Morley had thought thoroughly about this (although it seems simple to us now). They took a lot of time in preparation and thought; however, this experiment was not able to detect the aether. This experiment began a chain of experiments, which were based on this design, to detect the aether as people were still not able to let go of the theory of the aether. New modifications and more 'sensitive' equipment were used