Many-worlds and possible worlds in literature and art - Definition and Overview

The concept of possible worlds dates back to a least Leibniz. One of the earliest literary refernces occurs Voltaire's Candide. In it, Baron Thunder-Ten-Tronckh's tutor, Pangloss claims that we live in the best of all possible worlds,

Fanciful illustrations of the many-worlds interpretation of quantum mechanics and the unrelated concept of possible worlds are given by science fiction stories in which individuals are capable of viewing events on alternate paths of the universe or even travelling between alternate worlds or parallel universes; see, for instance, "Sliders". Mixing the concept of branching histories with that of time travel is also a common theme, such as in the motion picture series Back to the Future, which uses alternate realities.

Another kind of popular illustration of many worlds splittings, which does not involve information flow between paths, or information flow backwards in time considers alternate outcomes of historical events. For instance, on July 6, 2004 the New York Post incorrectly stated that U.S. Sen. John F. Kerry had chosen U.S. Rep. Richard A. "Dick" Gephardt as his running mate in the 2004 election. One could imagine that Kerry's choice split the "universe" in half and that the newspaper shows what a universe in which Kerry picked Gephardt would have been like.

More recently Robert Anton Wilson built his hilarious, complex Schrödinger's Cat trilogy around interpretations of quantum physics. The first book, The Universe Next Door, follows various characters through many worlds, while the second volume The Trick Top Hat connects them through nonlocality and the third, The Homing Pigeons, places them in an observer-created universe.

Borges' short story El jardín de senderos que se bifurcan ("The Garden of Forking Paths"), employs a similar concept. In the story, a Sinologist discovers a manuscript by a Chinese writer where the same tale is recounted in several ways, often contradictory, and then explains to his visitor (the writer's grandson) that his relative conceived time as a "garden of forking paths", where things happen in parallel in infinitely branching ways.