Most time travel science fiction is about traveling to the past, but something just as interesting is traveling to the future.
Just a little background: General and special relativity allow us to travel to the future at different rates than everyone around us. Time goes by slower in a stronger gravitational field. GPS satellites actually have to compensate for this. We are in a stronger gravitational field closer to earth so time goes by slower for us than the satellite.
Time also goes by slower the faster you travel. If John is in a spaceship traveling near the speed of light, he will age slower than his stationary brother Henry. GPS Satellites traveling about 7,000 mph also have to compensate for this.
So those are two methods to travel to the future, but the writing prompt is this:
What do time travelers to the future do when they get there?
They could travel 50 years or 1,000 years to the future. Everyone they left behind has aged and possibly died. They could be a historian for the future. They could bring some samples to the future for comparison on how much things have changed.
Why would someone travel to the future?
They don’t necessarily have to arrive in a dystopian future that needs saving. They may arrive in a typical day; everyone goes about their business, but the time traveler has become a relic. What problems does he face?