Question: What's the relation between gravity and Time?

Susan Cartwright answered on 16 Jun 2015:

In general relativity, gravity acts by causing the spacetime continuum to curve. This curvature causes the effects we see as gravity, and also affects the flow of time. Clocks in a gravitational field run slower than clocks in empty space. For this reason, the clocks in GPS satellites (which see less gravity than we do because they are at higher altitude) are deliberately set to run slow to cancel out this effect.