He ultimately returned to an intellectual investment in Newtonian gravity.

The easiest case for the application of a test particle arises in Newtonian gravity.

In Newtonian gravity, the source is mass.

Thus, Newtonian gravity is called a scalar theory.

Newtonian gravity, we might say, is not a contingent facet of our universe, but a necessary one.

Even at the surface of the Earth, the corrections to Newtonian gravity are only one part in a billion.

General relativity reduces to Newtonian gravity in the limit of weak gravitational fields.

Can we now say that we have "validated" Newtonian gravity?

Also, how does IV&V change the fact that the model is built on Newtonian gravity?

Forces such as Newtonian gravity, which depend only on the scalar distance between objects, satisfy this criterion.