bolen said:
a "realistic" space campaign would be confined to one system unless you allow FTL travel and then you are not "realistic again".
That's debatable. A lot of very interesting articles by theoretical physicists suggests some ways that FTL may be possible. Relativity itself suggests that wormholes can exist.
Of course it's not EASY, and no SF RPG currently in print does this.
You could also run a game with STL travel between stars, with sleeping colonists or whatnot.
If you don't know Einstein showed that time and space are relative. as you move faster, your clock slows down relative to someone else who is not moving. You can look this up on the web. do a google search on special relativity.
Most non-space opera sf that feature FTL does not simply assume that if you just push the gas hard enough, you are going to faster than light. This is really not the big issue.
The big issue is (also implied by relativity) if you can travel FTL, time travel is implicitly possible. If you assume some theoretical abberation that prevents this (or accept time travel and all the bugbears that go with it), you can make a fairly realistic go at a setting with FTL. Again, no published game does this that I am aware of and most hard SF games are happy to go with some black-box hyperdrive.
The other fact that makes science fiction "fiction" is how does one comunicate faster then light? This makes it hard to have intersystem commerce when it takes years to get a radio message.
Heh. You have just stumbled on the premise of Traveller. Hard or no, it is not explicitly necessary to have FTL radio comms to have commerce. After all, we had trade on earth in the age of sail long before Marconi was born.
Easy FTL comms make it that much harder to dismiss the time travel bugbear. If you can just radio your friend and tell him to duck before the bullet that killed him hits him, then you have instant causality problems. If you assume that the requirements for FTL travel are somewhat more baroque, you can explain that while the theory says one thing, in practice it doesn't work that way.
That may sound laughable, but don't dismiss it. There is a property of subatomic particles formed in pairs that when one particle is forced to assume a certain spin, the paired particle
instantly assumes the opposite spin. This is demonstratable fact. However, it is also implicit in the nature of the laws of physics governing these interaction that you will never be able to send intelligible in use this principle to make an FTL radio. (There are SF stories to this effect, though.)
Despite this, scientists have been able to send intelligible information faster than light. Using a quantum tunnel effect, they were able to send a symphony and some multiple of the speed of light... over a short distance, enough so that any macroscopic violation of causality is impossible.
In fact, unless there are wormholes or something else strange,[/b]
That there is "something else strange" is pretty much an assumption of any go at FTL in SF.
And as for wormholes, most theoretical physicists are convinced that they do exist in some form... just not necessarily a usable form.
(A bit fewer actually beleive that if you have the right stuff, you may even be able to use one...)
