My enlightening moment about general relativity: apples do not fall on the ground, instead, the earth is inflating, and the inflation of the earth is accelerating at 9.8 m/s^2. Eventually, the ground catches the apple.
Of course, you are going to tell me that the earth is not inflating, obviously, because it is still the same size after so many years.
But here is the trick: the earth is inflating at the same rate as spacetime contracts. If the earth didn't inflate, the contraction of spacetime would have collapsed it into a black hole.
Note: It is related to Einstein's elevator thought experiment. Here, the inflating earth replaces the rocket powered elevator.
Note 2: If the idea of an inflating earth bothers you, I suggest you start considering that the earth is flat, seriously! Flat Earthers took Einstein's thought experiment quite literally and consider the Earth to be a disk that is continuously accelerated upwards. And in fact, if free fall trajectories were parabolic, that would be the correct explanations. In reality, because the earth is not flat, free fall trajectories are elliptic, though it is only apparent on a large scale.
The thing is, I watched the French version and I didn't know an English version existed, that's why I didn't post it here, French speakers are, I believe, a minority.
And BTW, the French channel has an 8 part explanation of the maths behind general relativity that is the best I have ever seen. It is on a level above most pop science video since it actually shows the equations, tensors, etc... but the explanations are actually quite accessible.
Some interesting alternative viewpoints I've seen:
Matter continuously destroys spacetime at its location, sucking in the fabric of the universe.
The Universe isn't expanding; matter is shrinking. Light isn't redshifted on the way to us, it's just that our sensors are getting smaller relative to the unmodified wavelength of light.
I'm not sure how that hypothesis works out with things like black holes and gravitational lenses, friction, and a lot of other established physics. Somehow I figure people that believe in the expansion hypothesis will have some kind of workaround for those.
Yes - and it's observable in every rocket launch. When an astronaut is pushed back against their seat, they feel artificial gravity caused by the exhaust behind them inflating faster than the Earth normally does.
That the big idea behind Einstein field equations: energy (and mass because E=mc2) curve spacetime and spacetime curvature affects the energy fluctuations (and the way things move).
Because both terms of the equation affect one another, solving it is complicated but here, the result is that spacetime contracts to the center of the earth.
Of course, you are going to tell me that the earth is not inflating, obviously, because it is still the same size after so many years.
But here is the trick: the earth is inflating at the same rate as spacetime contracts. If the earth didn't inflate, the contraction of spacetime would have collapsed it into a black hole.
Note: It is related to Einstein's elevator thought experiment. Here, the inflating earth replaces the rocket powered elevator.
Note 2: If the idea of an inflating earth bothers you, I suggest you start considering that the earth is flat, seriously! Flat Earthers took Einstein's thought experiment quite literally and consider the Earth to be a disk that is continuously accelerated upwards. And in fact, if free fall trajectories were parabolic, that would be the correct explanations. In reality, because the earth is not flat, free fall trajectories are elliptic, though it is only apparent on a large scale.