[Zaak]

Can you phrase that question in a way that takes relativity into account? In particular, what do you mean by ticks being synchronized between two observers, when there's no such thing as objective simultaneity?

[criddell]

Two observers in the same inertial frame can share a clock, can't they?

[Zaak]

I believe so. I had assumed you were referring to the general case, sorry about the misunderstanding.