Last week I started talking about science in sci-fi worldbuilding. I have loads more to say on this topic, but thought I should clear up some things early on in case I come across as all pompous and preachy.
This is not meant to be a "thou shalt" set of posts.
Yes, I happen to think that a good appreciation of science is important to convincing worldbuilding, especially if your aim is to be taken seriously by scientifically-literate readers. If you fall into this category, then I hope you find a nugget or two to take away.
As a reader, I get a visceral reaction to things that strike me as absurd, and I've got a few pet peeves to talk about. But I'm not advocating slavishly following known science and squashing creativity. There are so many ways to stretch and extrapolate the world of science that you can be imaginative beyond belief while still being convincing.
But that is not the only option. I think it's quite possible to write sci-fi with a flagrant disregard for good science. The only inviolable rule in writing is "do what works", so under what circumstances might this approach work?
First off, you can often afford to play fast and loose with the rules for comic effect. For example, Harry Harrison's novel Bill, the Galactic Hero, introduces the Bloater Drive. Meant to provide a way around the speed of light limitation, it of course does nothing of the sort, but that doesn't matter because the novel is satirical and the science is visibly not meant to be taken seriously. Similarly, Douglas Adams brings out one whacky idea after another (my favorite is the "Somebody Else's Problem field) to great effect.
But note that, even here, the authors pay enough lip service to science - even though it's firmly tongue-in-cheek - that I suggest this is an example of knowing the rules first in order to break them properly.
Another approach, which many authors use with at least some elements of their story, is to simply brazen it out. Present the outcome and move on. Leave it up to the reader to fill in the gaps to their own satisfaction. This sleight of hand works time and again for minor pieces of technology, or for common devices such as FTL travel which everyone accepts as a necessity for most stories. Here it is. Deal with it. Move on.
Again, I think the amount of latitude you can safely assume depends on what kind of story and audience you are aiming for. I reckon the softer, space opera, end of the spectrum is more forgiving. If you are looking at realistic hard sci-fi then abuse the science at your peril.
This gets trickier when a major story premise hinges on dodgy science. Readers are likely to be less forgiving, but a good storyteller can still get away with it if the story itself is so engaging that readers either don't notice, or choose to forgive and forget.
Having said all that, I still believe that a foundation in scientific principles (note, this is not the same thing as the current state of scientific understanding!) can help make things more credible. Every whopper you ask the reader to swallow raises the bar for acceptance, so why do that to yourself unnecessarily?