If gravity slows time, how and are they linked?
t = t_f sqrt(1 - 2GM/rc^2) M is the mass, r is the distance from centre of mass
simple answer - because that's what general relativity says.
complex answer - because thats the way the universe works.
Yep that clears it aaaaall up.
If you want to work out how much to adjust your GPS satelite clock, or how much longer you will live on the top floor of the apartment - then the equation tells you.
As to why, there are answers involving space time tensors, kerr metrics, relativistic frame dragging etc - but they pretty much come down "because it does" but with more maths.
Ok it's complicated.
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