Originally Posted by bill_mchale
Hard Science Fiction, as opposed to other kinds (and not to suggest the other kinds are any less worthy of reading) has to, imho meet a couple of criteria...
Personally I don't agree with that definition of "hard" SF. "Hard," as opposed to "soft," SF, is simply SF in which the technology is well-researched, based on current knowledge and accepted theory, and presented in a realistic fashion consistent with that knowledge and theory. For instance, hard SF would generally NOT include faster-than-light drives (Star Trek), since that is still considered effectively impossible given our knowledge of current and possible science and technology. It could include clones (Jurassic Park), but would not include superheroes.
Another good hard SF series would be Nancy Kress' Beggars trilogy: Beggars in Spain
; Beggars and Choosers
; and Beggars Ride