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:So I'll look at that and try to clean it up.  And not have one of the approximations in the text while another is in a footnote.  That's just dumb.  Thanks for pointing out the problem.  [[User:SamHB|SamHB]] ([[User talk:SamHB|talk]]) 16:32, 4 September 2018 (EDT)
 
:So I'll look at that and try to clean it up.  And not have one of the approximations in the text while another is in a footnote.  That's just dumb.  Thanks for pointing out the problem.  [[User:SamHB|SamHB]] ([[User talk:SamHB|talk]]) 16:32, 4 September 2018 (EDT)
 
::I've looked it over, and I "sort of" stand by my original formulas.  I think things are confused by the symbol "a".  In modern relativity textbooks that's the Schwartzschild radius, (also know as the "gravitating radius") but in Einstein's paper it was the semi-major axis of the ellipse.  (You remember a and b being the semi-major and semi-minor axes of an ellipse from high school, right?  That's what Einstein was using.)  Now the reason I say "sort of" is that my supposedly nice approximation of <math>\frac{3GM}{c^2 a(1-e^2)}</math> was already simplified, by me, from what was in Einstein's paper.  And that was an approximation in any case.  The only way to get the really precise theoretical prediction is to solve numerically for a geodesic, by computer.  Thet's what the Pijpers paper is comparing with the experimental measurements.  [[User:SamHB|SamHB]] ([[User talk:SamHB|talk]]) 01:17, 5 September 2018 (EDT)
 
::I've looked it over, and I "sort of" stand by my original formulas.  I think things are confused by the symbol "a".  In modern relativity textbooks that's the Schwartzschild radius, (also know as the "gravitating radius") but in Einstein's paper it was the semi-major axis of the ellipse.  (You remember a and b being the semi-major and semi-minor axes of an ellipse from high school, right?  That's what Einstein was using.)  Now the reason I say "sort of" is that my supposedly nice approximation of <math>\frac{3GM}{c^2 a(1-e^2)}</math> was already simplified, by me, from what was in Einstein's paper.  And that was an approximation in any case.  The only way to get the really precise theoretical prediction is to solve numerically for a geodesic, by computer.  Thet's what the Pijpers paper is comparing with the experimental measurements.  [[User:SamHB|SamHB]] ([[User talk:SamHB|talk]]) 01:17, 5 September 2018 (EDT)
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::::I agree that it's an approximation, and a reasonable one for these purposes, but that 3GM/... approximation is ''per radian'' of rotation, so the precession over an entire orbit (2π radians of rotation) is 2π(3GM/....), or <math>\frac{6piGM}{c^2 a(1-e^2)}</math>. That can be converted directly into arcseconds per Earth century. Incidentally, how do you get a π to show up in an equation?--[[User:Brossa|Brossa]] ([[User talk:Brossa|talk]]) 23:23, 5 September 2018 (EDT)
    
:::Not even top relativists claim that the advance of the perihelion of Mercury proves the General Theory of Relativity anymore.  Once the divergence between more accurate measurements and the theory began occurring nearly 15 years ago, relativists stopped reporting data about this.  The Wikipedia entry on this displays a style of everything except confirmation by the data of the theory.  Instead, it talks about historical motivation and uses [[liberal style]] like "consistent with" rather than "confirms".  Its citations are then more than a decade old. See [https://en.wikipedia.org/wiki/Tests_of_general_relativity#Perihelion_precession_of_Mercury].--[[User:Aschlafly|Andy Schlafly]] ([[User talk:Aschlafly|talk]]) 12:13, 5 September 2018 (EDT)
 
:::Not even top relativists claim that the advance of the perihelion of Mercury proves the General Theory of Relativity anymore.  Once the divergence between more accurate measurements and the theory began occurring nearly 15 years ago, relativists stopped reporting data about this.  The Wikipedia entry on this displays a style of everything except confirmation by the data of the theory.  Instead, it talks about historical motivation and uses [[liberal style]] like "consistent with" rather than "confirms".  Its citations are then more than a decade old. See [https://en.wikipedia.org/wiki/Tests_of_general_relativity#Perihelion_precession_of_Mercury].--[[User:Aschlafly|Andy Schlafly]] ([[User talk:Aschlafly|talk]]) 12:13, 5 September 2018 (EDT)
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