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Old 30-October-2007, 05:43 PM
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Quote:
Originally Posted by Burt View Post
On light orbiting a black hole, Pamela said that light can orbit at half the Schwarzschild radius. Isn't that rather at 1.5 times the Schwarzschild radius (r = 1.5Rs = 3GM/c^2)?
No, she definetly said half the Rs, though that does mean inside the horizon and is thus somewhat speculative, and she said that quite clearly, too.

If you put v = c in the circular orbit eq. and solve for r, you'll get
r = GM/c^2 = 0.5Rs.

I'm not sure about more elliptical orbits, but I don't think they can lie outside the horizon either.

Steve had some interesting points there above, but I don't think I wanna dislocate my brain just now...
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