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nsomaru

As a layman reading this, it’s funny. Because I do not need gravity proven to me from first principles ;)

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Proven is the wrong word. You cannot prove a theory.

Deriving a description of gravity from first principles would be more appropriate

*an empirical theory.

I can certainly prove things about, say, addition.

if you mean you can prove 2+2==4, it's actually tautology: | | + | | == | | | |

no like, "addition is closed over the integers" is something you can show to be True (for all members of an infinite set, no less -- so it's not empirical.)

And yet, funnily enough, your phone needs a more thorough understanding of gravity than you do. The GPS system must correct for relativistic effects that cause the atomic clocks to shift relative to ground.

Isn’t this corrected by the satellites themselves?

Mostly, but there are still correlations between the satellites that are corrected by the receiver.

The Earth's gravity field is not deterministic.

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