The perception of gravity in general relativity (GR) can sometimes seem contradictory or confusing because it challenges our classical intuition about forces. It is important to note that Einstein's theory of general relativity revolutionized our understanding of gravity, introducing a new conceptual framework.
In general relativity, gravity is described not as a traditional force but as the curvature of spacetime caused by mass and energy. According to this theory, massive objects like stars and planets curve the fabric of spacetime around them, and the motion of other objects is influenced by this curvature. In this sense, the presence of matter tells spacetime how to curve, and the curvature of spacetime tells matter how to move.
When physicists say that gravity is not a force in the context of general relativity, they mean that it is not a force in the traditional sense of a physical interaction between objects mediated by particles (like electromagnetic forces). Instead, the effects of gravity are described by the curvature of spacetime, which determines the motion of objects within it.
However, it is also possible to describe the effects of gravity in a Newtonian framework, where it is treated as a force acting between massive objects. This Newtonian approximation works well in certain situations, such as when dealing with relatively weak gravitational fields or objects moving at low speeds compared to the speed of light.
So, while general relativity offers a more fundamental understanding of gravity as the curvature of spacetime, Newtonian mechanics can still provide accurate predictions in many situations as an approximation of general relativity.
The apparent contradiction arises when people try to reconcile the two frameworks without recognizing their distinct conceptual foundations. It is essential to understand that gravity is not a traditional force in general relativity but can be approximated as such in specific contexts using Newtonian mechanics. The perspective one adopts depends on the level of precision and accuracy required for the specific scenario under consideration.