Science fiction without the science just becomes, you know, sword and sorcery, basically stories about heroism and not much more.
Michio KakuCesium, iodine from the Chernobyl reactor accident went around the world many times and everyone on the Earth has a piece of Chernobyl in their bodies, but it's very tiny - too small to cause much damage.
Michio KakuWormholes were first introduced to the public over a century ago in a book written by an Oxford mathematician. Perhaps realizing that adults might frown on the idea of multiply connected spaces, he wrote the book under a pseudonym and wrote it for children. His name was Charles Dodgson, his pseudonym was Lewis Carroll, and the book was Through The Looking Glass.
Michio Kaku