Albert Einstein discovered relativity theory in the early 1900s which revealed that the passage of time is not the same everywhere in the universe. Clocks move faster or slower than the earth's clocks depending mainly on their velocity as a fraction of the speed of light. The rate of time passage not being the same everywhere is very difficult for we humans to either understand or accept. Nevertheless, it is a law of nature that has be verified in many ways.
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Video Length = 9 minutes