A free falling body doesn’t experience gravity but is moving relative to a stationary observer. This observer experiences gravity. – check.
An accelerating body experiences “gravity” and a stationary body observed by the accelerating body appears to be in motion. – check.
There’s a Veritasium video that covers this: [Why Gravity is NOT a Force](https://youtu.be/XRr1kaXKBsU).
Here’s where it gets a bit mind-bendy though. If the surface of the earth is stationary, why is it pushing up on our feet like the floor of an accelerating rocket would? Is it because although it is stationary relative to our space, it *is* moving through TIME?
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That’s it – both you and the Earth are moving through time and your paths are intersecting.
Everything in the universe is naturally moving through space and time in a straight line at a constant rate. Gravity warps space and time, bending and curving it such that objects moving straight ahead see their path curve. It’s still a straight line, but it’s a straight line in curved spacetime. We call this a geodesic.
In order for an object to deviate from its geodesic requires some kind of force. When the thrusters of a rocket activate the rocket begins to accelerate, and the floor of the rocket begins pushing you upwards. The force of the rocket pushing you upwards is forcing you to deviate from the geodesic path you would have been taking had the rocket not been there.
So how does this relate to gravity?
Imagine an apple falling from a tree and onto the ground. The apple, which was previously motionless, begins moving through the three dimensions of space until it eventually hits the ground, only accelerating once it actually reaches the ground. How is that possible though? If gravity isn’t a force how was the apple able to begin moving in the first place?
Well remember, even though the apple was previously motionless through space it was always still moving forward through time. Once the apple releases from the tree it continues to move forward in time, following a path from present to future. Because gravity curves space *and time* towards the Earth’s center of mass the apple, over time, will begin moving closer and closer towards the ground. Even though the apple reaches the ground it still wants to continue to follow this geodesic path but the Earth’s surface is hard and it pushes against the apple, preventing it from following its natural path. It’s for this reason that the apple doesn’t register an acceleration until it reaches the ground – while falling it was following it’s natural path through spacetime. The Earth, which is also moving forward through time, is pushing against the apple and moving it off it’s natural trajectory.
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