Can Varying the Gravitational Constant Mimic General Relativity's Effects?

[John15]

Hope this is the right forum as I am having a little trouble finding my around the site.
Just a thought and I don't know if it makes sense but could the results on gravitation in GR be duplicated using a variable gravity constant in Newtonian. I was thinking of using something like density to vary the GC.

 

[Mentz114]

There's no variation of Newtonian gravity that reproduces GR. There have been attempts made, like introducing propagation delay, varying G etc.

Newtonian gravity is rather like GR without spatial curvature, where only the time-curvature is operating. The weak field limit of GR approximates Newtonian gravity very closely, so it's more a case of how Newtonian gravity comes from GR rather than the other way around.

 

[John15]

Can I assume that includes giving all different density/velocity/masses and the space inbetween differing g constants

 

[Mentz114]

Can I assume that includes giving all different density/velocity/masses and the space inbetween differing g constants

I don't have enough knowledge about the topic to answer that, even if I understood it.

 

[Dale]

Hope this is the right forum as I am having a little trouble finding my around the site.
Just a thought and I don't know if it makes sense but could the results on gravitation in GR be duplicated using a variable gravity constant in Newtonian. I was thinking of using something like density to vary the GC.

No. That would be a scalar field and AFAIK, the GR field cannot even in principle be represented as a scalar field except in the case of static spacetimes.