Try imagining a fictional conversation between Issac Newton and Albert Einstein:
"The apple falls toward the ground because the gravitational force of Earth makes it so," as you expect Newton would argue. To that, Einstein then responds: "The apple falling toward the ground is just an illusion; instead, it maintains its own status of motion as Earth moves to intercept it."
Most of you would likely agree with Newton's interpretation while considering Einstein probably loses his mind. However, the father of the general theory of relativity does have a irrefutable point if you care to dig a little deeper into our perception of reality.
The key to unlocking Einstein's perception of this event is the idea of curved spacetime. An object has a tendency to maintain constant in velocity and traveling trajectory, a.k.a. inertia. According to Newtonian mechanics, only when a force, such as gravity, is applied on the object would it then change its course, as depicted in events like an apple falling from a tree or a comet hitting a planet.
However, in general relativity, the existence of gravity is not required: objects with mass bend the spacetime around it. The bigger the mass (such as Earth or the Sun), the more pronouced the curvature. Therefore, from the moment it gets detached from a branch, the famous "gravity" apple acquires and maintains its inertia frame of motion, as witnessed by an inertia bystander. Its seemingly floor-bound trajectory is not the result of the gravitational force but the intensely warped spacetime created by Earth's mass.
So if you're taking Einstein's point of view, which's shaped by the general theory of relativity (it's proven valid by numerous experiments and scientific observations, mind you), then you would realize that the gravitational force is just a facade that covers up the big and small wrinkles in the fabric of spacetime.
Source: Veritasium via Youtube
