Ive started reading another book today which is about the science theories behind the stuff we see in doctor who. Some of the topics covered are stuff like time travel, teleporting and various other things.
A teaspoon and an open mind - the science of doctor who
Author = Michael White
first publish date was for 2005 by the penguin group
So far, Im halfway through the first chapter which is about the theory of time travel and the various scientific methods by which that may or may not be possible - but the book says it could take centuries before it happens.
Theres also a chapter discussing what aliens could actually look like too.