You’re writing a tale about a band of teens turned into miniaturized humans, and there’s a scene where they’re sitting around a fire made from matches, watching as the night wears on. And suddenly, you say: wait a minute! Fire doesn’t last that long! A bunchy of matches would burn for only a few minutes tops!
Yes. And? If you want to go all hard sci-fi, miniaturized people shouldn’t exist. For that matter, even many “hard” sci-fi settings include things like FTL and generated gravity, usually covered with some comments about how theories in the present turned out to work. But in truth, it’s likely that FTL is just as much fantasy as Harry Potter.
None of which matters. If people are buying your book about tiny people, they’re buying into the fantasy. As long as you’re consistent, only a very few are going to start muttering about how this couldn’t really happen. The rest will roll their eyes and say: Duh, if we wanted reality we’d be watching CNN.
So remember, unless you’re writing a very hard sci-fi story, don’t let science be your tyrant. Sometimes it’s okay to just wink at people and know that they’ll be understanding of your setting because they didn’t come to you for an education in science—but to have a fun read.
