Because I am starting with Issac Newton, I thought gravity might be a good place to begin cataloging the history of science. However, the more I read about it, the more it seems like Newton's gravity (or gravitation) does not even exist. I cannot find any references to anyone measuring Newton's force of gravitation.
It would seem that Newton simply imagined that gravitation exists, because he needed a theory to explain why all physical bodies attract each other. In other words, there is nothing anywhere that he could measure that he could call gravity, but there are these effects that he could measure (physical bodies attracting each other) that he needed to explain. So he proposed that there is an invisible force that pulls all matter together. Is this at all correct? Can anyone confirm or deny this?
After I figure out Newton's gravitation, it would seem that the next step in understand gravity is to figure out Einstein's general relativity. According to Wikipedia
, "In general relativity, the effects of gravitation are ascribed to spacetime curvature instead of a force."