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time dilation
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time dilation
Understand the concept of time dilation in special relativity as explained by Albert Einstein and Richard Feynman
Two graphs illustrate effects of relativity as velocity approaches the speed of light: the left graph shows time dilation increasing sharply, while the right graph shows length contraction decreasing, both as functions of velocity.
Explore three simple ways and three complicated ways of time traveling
Learn about the six famous paradoxes in philosophy and science
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Italian-born physicist Dr. Enrico Fermi draws a diagram at a blackboard with mathematical equations. circa 1950.
Physics and Natural Law
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time dilation

physics
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time dilation, in the theory of special relativity, the “slowing down” of a clock as determined by an observer who is in relative motion with respect to that clock. In special relativity, an observer in inertial (i.e., nonaccelerating) motion has a well-defined means of determining which events occur simultaneously with a given event. A second inertial observer, who is in relative motion with respect to the first, however, will disagree with the first observer regarding...

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