time dilation: Quick Facts

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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.

Understand the concept of time dilation in special relativity as explained by Albert Einstein and Richard Feynman

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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time relativity time perception twin paradox 22 Questions About Time and Timekeeping Answered dynamical time geologic time week month day solar time year

Italian-born physicist Dr. Enrico Fermi draws a diagram at a blackboard with mathematical equations. circa 1950.

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