"Even Isaac Newton, said to be the discoverer of gravity, knew there were problems with the theory. He claims to have invented the idea early in his life, but he knew that no mathematician of his day would approve his theory, so he invented a whole new branch of mathematics, called fluxions, just to "prove" his theory. This became calculus, a deeply flawed branch having to do with so-called "infinitesimals" which have never been observed.

"Then when Einstein invented a new theory of gravity, he, too, used an obscure bit of mathematics called tensors. It seems that every time there is a theory of gravity, it is mixed up with fringe mathematics. Newton, by the way,was far from a secular scientist, and the bulk of his writings is actually on theology and Christianity. His dabbling in gravity, alchemy, and calculus was a mere sideline, perhaps an aberration best left forgotten in describing his career and faith in a Creator."

https://ncse.ngo/gravity-its-only-theory