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Schwarzschild radius calculation

  1. Jan 28, 2016 #1
    Is this the proper formula for calculating the Schwarzschild radius of a black hole?
    rs = 2GM / c2
    If it is not, or if anyone has one that might work better, could you refer it to me?
  2. jcsd
  3. Jan 28, 2016 #2
    That's correct.
  4. Jan 28, 2016 #3
    Thank you!
  5. Jan 29, 2016 #4


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    I'd just add that in Physics now days, M is a systems' rest mass while gravitational effects depend on the total energy. So, the equation is precise only for a stationary mass, I believe.
  6. Feb 3, 2016 #5


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    For an arbitrary system, the M would be the mass measured by considering the orbit of a distant body of known mass. In this sense, the formula is universally true. For a system of bodies still far enough apart so curvature is small (and pressure and EM fields are insignificant), it is approximately the SR invariant mass of the system - which will include the KE of the bodies in the overall COM frame.
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