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Comment by sghiassy | Hacker News Reader

Gravity isn’t a force, it’s a curvature of space time

It's weird how mass just somehow perturbs spacetime creating a 3D whirlpool down which everything falls without using any energy in the process. That theory about mass actually only accelerating time and then the time dilation between atoms causing the force of gravity as a consequence is pretty nuts.

Makes you think there really ought to be a way to "stick" onto spacetime and stop yourself from being accelerated, much like pulling the parking brake on a hill. Maybe one just needs a time machine.

You can put the surface of a planet between you and the bottom of the whirlpool like us humans do.

Yeah but that's the lazy solution that's not really all that useful. I mean it's definitely useful to not keep falling towards the planet core, but for other less mundane uses.

If you want to "stick" to spacetime, there must be a reference frame that is somehow different from all the others. There is presently no experimental evidence for any such frame, despite a century or two of searches by very clever people.

Well maybe not literally, just in practical terms. If it's a time gradient that causes an object to accelerate, then if you can apply a reverse gradient that would just cancel out the forces. But yes, one would need to first figure out how to do that without an equivalent amount of mass on the other side, if it's even physically possible.

Here's a stupid idea that's based on my definitely flawed understanding of relativity: If having high relative velocity causes time dilation, then wouldn't spinning a disc at relativistic speeds cause that same time gradient? Maybe we just need 99.9% c rad/s fidget spinners to float in the air just like bricks don't.

Found the video on this theory: https://www.youtube.com/watch?v=UKxQTvqcpSg

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