Originally posted by Peterdevis
I think a Rolex will probably tick a little faster in space, since there are no gravitational forces pulling down on its gears and their shafts, so they won’t experience as much friction in space. But the speed up will not match the same speed-up rate as an atomic clock, because the Rolex speed up is a large-scale “mechanical” function, while an atomic oscillation speed up operates by quantum mechanics rules.
Regarding a Rolex or any kind of balance-wheel watch or clock, think of it this way: Put the watch inside a rapidly spinning centrifuge, and notice that the higher the g forces, the more friction is placed on the bearings and the gear shafts. This will tend to slow the watch down a little. However, if you put an electronic watch in your refrigerator freezer, that will slow it down a little, for thermodynamic and quantum mechanics reasons. Put a pendulum clock high on a mountain and it will slow down. Put an atomic clock in a valley and it will slow down.
These different types of clocks will slow down and speed up for different reasons, because different laws of physics apply to the different types of clocks.