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Relativity - Simultaneity

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

This movie explains an idea called "simultaneity". Simultaneity is an important part of Albert Einstein's theory of relativity. Imagine two people who are moving very, very fast relative to each other. Now imagine they see two flashes of lightning. The two people might disagree about when the lightning flashes happened. One person might say they happened at the same time. The other person might say that they happened at different times. According to Einstein, both people could be right!

(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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