Special Theory of Relativity

Einstein's version of the laws of physics, when there is no gravity. The two fundamental concepts in the foundation of this theory are equality of observers, and the constancy of the speed of light. The first of these means that the laws of physics must be the same, no matter how quickly an observer is moving. The second means that everyone measures the exact same speed of light. This theory is useful whenever the effects of gravity can be ignored, but objects are moving at nearly the speed of light. It has been successfully tested many times in particle accelerators, and orbiting spacecraft. For objects moving much more slowly than light, Special Relativity becomes very nearly the same as Newton's theory, which is much easier to use.

Four Areas of Science


Go, wond'rous creature!
Mount where Science guides,
Go, measure earth, weigh air,
    and state the tides;
Instruct the planets in
    what orbs to run,
Correct old Time,
    and regulate the Sun.

Alexander Pope's
An Essay on Man

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About SXS

The SXS project is a collaborative research effort involving multiple institutions. Our goal is the simulation of black holes and other extreme spacetimes to gain a better understanding of Relativity, and the physics of exotic objects in the distant cosmos.

The SXS project is supported by Canada Research Chairs, CFI, CIfAR, Compute Canada, Max Planck Society, NASA, NSERC, the NSF, Ontario MEDI, the Sherman Fairchild Foundation, and XSEDE.

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RT @KeefeMitman: Nearly 50 years ago, my advisor, Saul Teukolsky, showed how a perturbed black hole rings down to a state of equilibrium. T…

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