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Advance of perihelion

  1. Jul 7, 2008 #1
    The formula for the advance of the perihelion of Mercury is given as :
    [tex]\Delta T = \frac{c^{2}a(1-\epsilon^{2})P}{3GM_{sun}}[/tex]
    for the time taken to advance through [tex]2\pi[/tex]. I was wondering what approximations were made from the Schwarzschild solution to get to this result.
  2. jcsd
  3. Jul 8, 2008 #2


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    The full derivation takes a couple of pages and the only approximation is near the end, when a Newtonian value is substituted into the full EOM with the assumption that

    [tex] \frac{M}{r} << 1[/tex]

    An oscillating term is dropped from the result of this substitution. Please see any standard textbook of GR.
  4. Jul 8, 2008 #3


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    "The Mathematical Theory of Relativity" written by Sir Arthur Eddington, in the 1920's and still available through Dover Books, devotes a chapter to the derivation of the "advance of periheliion".
  5. Jul 8, 2008 #4
    Thanks for the input guys
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