How accurate are Newton's formulas concerning Gravity, and other questions

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The discussion focuses on the accuracy and limitations of Newton's gravitational formula, Fg = G M1M2 / r², particularly in binary systems. Participants express skepticism about the reliability of various algebraic gravity formulas and seek alternatives that define gravity and energy. The conversation highlights the need for clarity regarding the constraints and assumptions inherent in Newton's formula. Additional equations, such as g = - GM / [D² (1 - 2 GM / (rC²))] and g = - MG hat r / r², are mentioned as examples of interest. The thread invites further contributions of algebraic gravity formulas for a deeper understanding.
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Binary System

Fg = G M1M2 / r2 M1d1 = M1d2

I don't have non-binary gravity formulas, so if you know any post them here (or any other algebraic gravity formulas you may be aware of)

I am interested in algebriac formulas that define gravity and energy, but I am a bit skeptical and not always sure which formulas I can trust.

Other than being for a binary system, does Fg = G M1M2 / r2 have any constraints, assumptions, limitations, or contradictions (problems)?
 
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thanks A.T. ... from your link, and following the links on tied link pages I found the equations:

g = - GM / [D^2 (1 - 2 GM / (rC^2))]; and

g = - MG hat r / r^2


these are the types of gravity equations I'm looking for, and any others are greatly appreciated, should anyone know any that are also in algebraic form
 
try kepler
 
check out MOND on wiki , not that i agree
 

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