I have always enjoyed science fiction. But one of the things that disturbs a good skeptic like me is the number of elements in science fiction books that I am pretty sure are utterly impossible. In other words, they are not a fictional science, but magic.
I am happy to accept something that we cannot achieve today, but which might be possible, such as suspended animation. But what of all those things which, according to our appreciation of the lawsd of physics, are utterly and totally impossible? I can think of a few.
1. Faster than light travel. (Or radio).
2. Tractor beams.
3. Energy fields as armour.
4. Inertial compensators.
5. Time travel into the past.
6. Psychic powers.
And so on.
I guess an author has the right to adopt one or two of them as 'artistic license' and pretend that some time in the future humanity might have a breakthrough that permits an action currently considered impossible. But how far should an author go in this? How blatant can the author be? Is this not an affront to credibility? At what point does a scifi book become fantasy?