
Parallel universes are big in science fiction, popping up in shows ranging from the “Terminator” movies to “The Man in the High Castle” to “Hot Tub Time Machine.” And strangely enough, those fictional tales have their parallels this year in a pair of nonfiction books about parallel universes.
We’re leading off our annual holiday roundup of science books with “The Number of the Heavens” and “Something Deeply Hidden,” and continuing the theme with six other thought-provoking picks about other realities, fictional and factual. If that’s not enough, you’ll also find links to geeky book recommendations from outside sources, plus our own top picks from previous years.