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Science, Evolution, and Creationism, by the National Academies, focuses on teaching evolution in today's classrooms. Check out the other publications in our online store.

Relativity - Time Dilation

This movie explains the concept of "time dilation", which is part of Einstein's theory of relativity.
Image courtesy of Trent Schindler, National Science Foundation.

This movie explains an idea called "time dilation". Time dilation is an important part of Albert Einstein's theory of relativity. Imagine two people who are moving very, very fast relative to each other. Each of them will think that time is passing more slowly for the other person than it is for herself or himself. In other words, they will think the other person's clocks are running more slowly. Pretty strange, huh? That is just one of the very odd things that Einstein's theory of relativity says is true!

(Note: If you cannot see the movie you may need to download the latest QuickTime player.)

Last modified May 29, 2008 by Randy Russell.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF