Category:Novels about parallel universes

Novels about parallel universes, hypothetical universes co-existing with one's own, typically distinct in some way. The sum of all potential parallel universes that constitute reality is often called the "multiverse". Another common term for a parallel universe is "another dimension", stemming from the idea that if the 4th dimension is time, the 5th dimension—a direction at a right angle to the fourth—is a direction into any of the alternative spacetime realities.