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Schwarzschild metric

  1. Jan 28, 2015 #1
    How do you obtain this equation M=Gm/c^2. What does M stand for? Is is newton law at infinity? Again what is this newton law at infinity?
  2. jcsd
  3. Jan 28, 2015 #2


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    Staff: Mentor

    M is just the mass of the black hole using units in which G and c are both equal to one.

    We don't have to make this substitution but if we don't we'll be schlepping factors of G and c around everywhere in our equations, and they're complicated enough already.
  4. Jan 28, 2015 #3
    Do you mind telling me a source for such derivation? Cause all the Internet gives is just the derivation of the schwarzschild radius.
  5. Jan 28, 2015 #4


    Staff: Mentor

    It's just a conversion factor from mass units to length units; ##Gm / c^2## converts the mass ##m## to an equivalent length. The Schwarzschild radius corresponding to ##m## is just twice that equivalent length.
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