An experiment which demonstrates verifies the prediction of time dilation by special relativity. Muons, which are short-lived subatomic particles, are created with enormous energy in the upper atmosphere by the interaction of energetic cosmic rays. Muons have a very short halflife in their own reference frame, about 2.2 us . Since they are travelling very close to c , however, time dilation effects should become important. A naive calculation would indicate that, without special relativistic effects, the muons would travel on the average only about 700 m before decaying, never reaching the surface of the Earth.
Observations reveal, however, that significant numbers of muons do reach the Earth.
The explanation is that muon is in a moving frame of reference, and thus time is slowed down for the muons relative to the Earth, effectively extending the halflife of the muons relative to the Earth, allowing some of them to reach the surface. NEXT N A to null experiment . All rights reserved.