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  • Why does E = mc2?

Gravitational Waves

  • Have we ever detected a gravitational wave?
  • Why should we care about gravitational waves?

White Dwarfs & Neutron Stars

  • Why is it "white dwarfs", rather than "white dwarves"?

Black Holes

  • How would we know a black hole is there if we can't see it?
  • Do black holes just hang around forever?
  • Do we know that black holes exist?
  • How much does a black hole weigh?
  • How big is a black hole?
  • Will the Sun turn into a black hole?
  • Wouldn't a Black Hole "suck up" everything in the Universe?
  • I thought nothing could escape a black hole, so how does it evaporate to nothing?
  • Do black holes make time travel possible?

Big Bang

  • What came before the Big Bang?
  • How old is the Universe?
  • How big is the Universe?
  • Will the Universe collapse back to a point again?

Other Questions

  • What do 108 and 10-21 mean?

Four Areas of Science


In the 1st year of the period Chih-ho, the 5th moon, the day chi-ch'ou, a guest star appeared...

Yang Wei-T'e, Imperial Astronomer of the Sung Dynasty, 1054 A.D.

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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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