• Why does E = mc2?

    This famous formula was Einstein's most intriguing prediction. Einstein made two assumptions: (1) all motion is relative — you can't be moving unless you're moving relative to something else; (2) everyone measures the same speed of light. With these two assumptions, and a little math, Einstein proved that the only way these two assumptions could be consistent with each other is if the energy E of a resting body with mass m is mc2.

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Now, here, you see, it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run twice as fast as that.

The Red Queen in Lewis Carroll's Through the Looking Glass

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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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