So. Time is weird, and something I never see any sci fi really address besides showing off that they know about relativity. Not only is time incredibly subjective to each planet (a "year" being defined in how long it takes for 1 planet to circle its star being completely different for every planet) but different species and cultures would develop their own measurements or maybe have a completely different understanding of time all together. There is after all a culture on earth that refers to the past being ahead of them and the future being behind them (they can see the past, thus it must be in front of them. They do not literally believe the past is in front of them chronologically it's just how they refer to it while most other cultures would say "time is behind us") and they have trouble coordinating with others from what I understand.
So. How would a multi-system Empire, let alone a galactic one, coordinate time in an efficient manner? No sci fi really talks about this just not acknowledging it as a problem.
My solution is simple:
Take a nuclear element, something with a rather long, concrete, and predictable half life. Make sure that it is something which is able to be freshly created in a lab. Then, divide that element's existence into a bunch of equal parts, where a single part, let's call them "ticks" for simplicity, is an agreed passage of time that cultures can use math to determine how many of their native units = one tick. Then use ticks as the universal time measurement. Clocks could simply be a device that measures ticks, displaying how many ticks have passed similarly as to how a clock shows how many minutes have passed. Once the clock hands, should it be one with hands, travel a full 360 around the element would have been depleted and all ticks used up only to be started again.
This would be something that every species capable of space flight would be able to comprehend, and most likely already measured, making the transitioning of their local units to ticks easy and efficient should they want to fully replace them, and at the very least they will be capable of producing some sort of calculator so that when they are given a number of ticks they can convert it to their local units.
I know this isn't particularly a big problem in sci fi, nothing is going to be ruined, and no universes are going to seem unrealistic because of this problem, but I was just thinking about how everyone on Chaos says "years, days, hours" etc even though they really mean nothing in the grand scheme of things.
Anyway. Thoughts?