Louis Essen

Louis Essen (* September 6, 1908; † 24 August 1997) was an English physicist.

He provided valuable input for the precise measurement of time and to determine the speed of light by building an electric resonant cavity, with which it was possible for him to inject microwave radiation into a closed, hollow metal cylinder. If the height is an integral multiple of half the wavelength, a standing wave is formed. The wavelength of the radiation in free space, in contrast to the cavity chamber, but in this case resonance of the microwave radiation in free space equally. In 1950 he published a value of 299,792.5 ± 1 km / s for the speed of light.

Food for decades was responsible for the British time standard. As a physicist, he had been interested from the beginning to the problems of relativity theory. He was a persistent critic of the special theory of relativity, in particular the concept of time dilation, which he refused strictly. He refused to take account of the clock synchronization, the Lorentz factor.