In the Star Trek universe there is no longer currency. People live their lives and act out of the greater good for society at large. There may be more to it, I love the show but I’m not extremely versed in the entire background of the universe. As it is the economy in a region as large as the US is almost impossible to manage properly. There are minimal differences in time and distance is infinitesimally small on a cosmic scale.
Imagine if we had civilization on Mars. You’d take that mere 6 hour difference (not including our friends in Hawaii or Alaska) in the US or 24 hour time difference globally and you’d need to synchronize that both with the nearly 25 hour day on Mars (different people being awake at different times) and the 6 minutes of time it takes at best for a beam of light to travel from Mars to Earth and back.
This is not to say for any cosmic radiation [or other variables] that might interfere with your messages either. Not too bad you might think. I find that already to be a difficult task. This doesn’t even cover that commerce would be moving on different projects, at different paces, for different populations. All these desynchronized things happening at once. You’d likely also have unique currencies because humans are anything if not predictable.
Perhaps we build some civilization either on or around Europa. That’s almost 4 times the length of an Earth day and between .5 and an hour for the round trip of data to travel. Or you could bounce information from Mars to Earth, certainly nobody on Mars would alter information traveling in from Europa to better their profits. Humans would never do that.
We then stretch out to the next solar system with a habitable planet. Either on Tau Ceti e or Tau Ceti f, these Solar Systems are 11.9 light years from our Solar System. This means there would be a 22 year span of time for data to be sent to and from Earth to them and back. That’s not counting the difference in time of day, commerce, etc. You couldn’t possibly build an economy off of this that is trans-solar.
After that we are looking at Gliese 581 d which is 20 light-years away or nearly half the human lifespan just for a single market update. Again this is all taking into account that we can’t even run an economy on a scale as small as the Earth. We are already at the upper limits of our ability to keep currency and keep people connected. When Space travel becomes a genuine thing it will likely mean the end of money.
It makes me wonder if a star trek future becomes currency less because they are more noble or because it is the only option? I suppose the end result is positive either way so what does it matter?
PS. I suspect once we have warp travel our technology will be so advanced that currency will seem petty. By then we could build just about anything from the particles in our surroundings and by disassembling other matter at the molecular level.