Everyone knows Grav is widely circulated on the 1-credit chip.
As for other galaxies, technically as Weylin said the Star Wars galaxy is set in a time line before the occurrences of our own galaxy so George Washington might not even be a twinkle in his father's eye yet.
As for knowledge of other galaxies, there would be no darkness mechanism for creating a metaphysics/scientific study of other galaxies but you could have a blast with intellectually framing IC and RPed knowledge of other galaxies.
Albert Einstein developed some theoretical notions that the progress of time can vary. He said some people could live in a faster time than others.
The passage of time could be at different rates, depending on the point of reference. Conceivably, the events of another galaxy occur in the future time of our galaxy.
The Star Wars galaxy could have been in the past but if we travel there, we might arrive at the future. That unpublished story that Hacov Ashfar mentioned sounds quite plausible. Time travel could be relativistic, using the physics of Einstein.