We all love them: stories celebrated as SF that aren’t based on “real science”. I realize that “real science” is a slippery concept – but I think that there are some sciences that are more…likely than others.
For example, John W. Campbell was a well-known proponent of psi powers. I avidly read the “Telzey” stories of James H. Schmitz in ANALOG in the early 70’s, when I first started reading the magazine (“The Telzey Toy” was the one I remember best). The early 21st Century has revealed true wonders of the human mind, for example, the discovery that adolescents are IN FACT crazy some of the time. (http://harvardmagazine.com/2008/09/the-teen-brain.html) But we haven’t yet been able to verify that true telekinesis or telepathy exist.
Likewise, H. Beam Piper’s marvelous works enthralled me when I was young (and old) but while an interpretation of quantum mechanics might allow for his fictional “Paratime” stories to exist in alternate timelines, they are, at the heart of them, scientifically unlikely. (http://en.wikipedia.org/wiki/Everett_many-worlds_interpretation)
Humaniform robots with transhuman intelligence have been a staple of SF since Karl Čapek introduced the word “robot” in his 1921 play, R.U.R. Isaac Asimov carried the idea to its logical conclusion creating a robot detective indistinguishable from a human in the person of R. Daneel Olivaw. Even so, practical Artificial Intelligence (AI) with a human-sized cranium and human-style mobility seems to have a number of very difficult hurdles to leap, leaving me to think that if it is not unlikely, then it is a very, very long way into the future. http://en.wikipedia.org/wiki/Artificial_intelligence
While I won’t stop reading SF and I’ve given the “mundane SF” sub-genre a try, I’d still like to see even more SF based on “real science” and the collision of real people and their real beliefs (you know which ones) with that science in a realistic, thoughtful way with biases suppressed and imagination alive.