Gdtyjr

So, in my post-apocalyptic novel, the world was caught up in an international war (basically WWIII), and all the world's nuclear superpowers launched their warheads and killed much of the global population. Ambient radiation from the nuclear fallout has caused humans to develop supernatural abilities.

And that is not science.

I totally get that radiation just hurts/kills people, it doesn't give someone the ability to manipulate life force or become pyrokinetic like I assert in my story. That's not scientifically possible.

But does my story need to be scientifically accurate or plausible? Will I lose readers because all they can think of is "that would never happen"? Can a story like mine with inaccurate/nonexistent science still be appealing?

Spiderman was bitten by a spider and developed spider-like abilities. Superman is from a different planet and afraid of a glowing rock, even if this human-like creature can shoot lasers from his eyes. The Incredible Hulk is... Hulk...

If you are looking for a non-comic example take a look at the Metro series. Post-apocalpyse after the nuclear war. Everywhere there are creepy mutants wandering around and people are living from pigs and mushrooms in the Moscow Metro. When reading it I wasn't thinking about realism - I was thinking about the interesting story and what the auther did with this unrealistic premise.

I could list dozens of books I have read that don't have a realistic premise. Especially once you introduce superpowers nobody will care. Your readers are not the ones to complain about non-realistic stuff if that is your premise. Nobody can force you to stick to reality.

Heck, I am currently reading something about a great war between dwarves and dragon-riding elves. My dragon army will grill your "physics" :D

There are lots of genres out there that don't care a bit about realism. Post-apocalypse radiation superheroes are definitely in one of those.

No, people won't say that, not even full time working scientists (like me). I know a great deal about genetics, I've published academic articles about it. That did not prevent me from enjoying the TV series "Heros" for several seasons. Supposedly their super-powers were due to "genetic mutations" (including immortality, time-travel, psychokinesis, irresistible "command" voice, fire-starting, invisibility, etc.)

That's B.S. to the power of infinity, but I get it, you need an explanation for your fantasy universe, and "Radiation" and "genes" are a stock answer, like "quantum" anything.

Personally, I'd embrace the magic. You are writing a fantasy, and in fantasy magic generally exists without explanation (rules of magic are common, magic systems are common, but where the actual "magic" comes from is just an assertion that something exists, like "life force", or "the force" in Star Wars, or whatever). You can do the same; just use your imagination and make something up. Meaning, the radiation isn't causing genetic mutations, it just released some kind of magic into the world and now some people are learning to use it. Maybe all the magic was used up, and now (due to the nuclear explosions) there is a fresh supply of it.