As a blogger on Amazing Stories, I do what I can to keep the magazine's age-old speculative spirit alive. Part of that is thinking of the most mind-bending writing prompts I can, regardless of natural or social science inspiration.
This month's is a purer science fiction than last month's. My psychology is better than my physics, but here's a physics-based prompt that anyone who grew up playing pinball should find fun:
Let me tell you a story about a place called Downland. In Downland, there are hills, ramps, staircases and elevators, much like in the real world. However, no one can ever go up them. Once you’ve gone down, you can’t return. You can walk on the level all you like, of course.
Does it matter whether your travel is voluntary or involuntary, such as being catapulted? What about changes in elevation (probably due to human intervention given how long topographic changes take naturally), like a Bottle Imp Paradox of sorts?
Much like Flatland, Downland is a place where one simple premise sets off an explosion of possibilities. What would you do with them? How would you react to visiting this world? What would you see? If you were a native, would you consider climbing a flight of stairs as fantastical as Earthlings consider flying?
There are more scenarios at that bolded link too.
So if this is your eternal future...
(from Wiki - oddly, from the article entitled "Stairs")