B Orbital Mechanics: GR vs Newton's Laws

[Peter Riedt]

9/1/2016 Orbital mechanics Wikipedia, the free encyclopedia
This reference states:
"General relativity is a more exact theory than Newton's laws for calculating orbits, and is sometimes necessary for greater accuracy or in highgravity situations (such as orbits close to the Sun)".

Can GR predict/calculate the trajectories of solar objects?"

 

[Lucas SV]

Yes, it can.

 

[PeterDonis]

Can GR predict/calculate the trajectories of solar objects?

Newton's laws are a weak field, low speed approximation to GR. So every scenario that you can predict with Newton's laws, you can predict with GR. In many applications in the solar system, the difference in the predictions between the two is too small for us to measure with our current technology. But there are enough cases where the difference is detectable for us to have confirmed with high confidence that GR is more accurate than Newton's laws wherever the two's predictions differ.

 

[Peter Riedt]

What are the GR formulas to calculate a planetary distance to the sun or orbital period around the sun or average velocity around the sun?

 

[PeterDonis]

What are the GR formulas to calculate a planetary distance to the sun or orbital period around the sun or average velocity around the sun?

This is covered in most GR textbooks, including how Newtonian gravity is derived as a weak field, slow motion approximation to GR. It is much too general a topic to address in a PF thread. If you have specific questions about statements in a specific acceptable reference (textbook or peer reviewed paper), please start a separate thread. This thread is closed.