A time dilatation experiment based on the M ssbauer effect

Some experiments are described in which the time dilatation at the tip of a high speed rotor is measured and compared with the expectations of relativity theory. Mössbauer sources and absorbers are attached to the centre and tip (or vice versa) of the rotor and the time dilatation deduced from the variation of gamma ray transmission with rotor speed. A technique is described whereby using a source absorber combination with an appropriate inherent frequency shift the experiment takes on the features of a null experiment. A result 2.1% ± 1.9% in excess of the expected dilatation is obtained.