2008/09/08 by J. H. Field, Field, J. H.
Physics and Astronomy · #FOS: Physical sciences #General Physics (physics.gen-ph) #physics.gen-ph
paper · pdf · doi:10.48550/arxiv.0809.1314
11 pages, 3 figures, 1 table. v2 minor correction, references updated
arxiv created 2009/02/05 · arxiv updated 2009/12/01
Observation of the decay of muons produced in the Earth's atmosphere by cosmic ray interactions provides a graphic illustration of the counter-intuitive space-time predictions of special relativity theory. Muons at rest in the atmosphere, decaying simultaneously, are subject to a universal time-dilatation effect when viewed from a moving frame and so are also observed to decay simultaneously in all such frames. The analysis of this example reveals the underlying physics of the differential aging effect in Langevin's travelling-twin thought experiment.