What is the Multiverse?
“Many and strange are the universes that drift like bubbles in the foam upon the River of Time.”
—Arthur C. Clarke, The Wall of Darkness
What if our universe is not the only one, but part of an infinite set of universes in a cosmic landscape? That’s one conclusion that many cosmologists and quantum physicists are pondering. For reasons that I will explore in this series of articles, the Many-Worlds Interpretation answers stubborn questions raised by quantum mechanics since its ascendency in the 1930s. From the enigmatic Schrödinger’s Cat to the famous double-slit experiment, quantum physics has confounded us. As Feynman advised, “If you want to understand quantum mechanics, just do the math …the ‘paradox’ is only a conflict between reality and your feeling of what reality ‘ought to be.’”
Yet, this still leaves me a little empty inside, wanting a more intuitive answer. Perhaps we have a better understanding of these paradoxes by envisioning multiple universes laying side-by-side like sheets of paper, hidden within other dimensions outside of our everyday experience. If M-theory proves sound, we’ll face the uncomfortable notion that even the familiar dimensionality of three-dimensional space and time must be expanded to eleven dimensions. However weird this may seem; this idea is not new.
In 1584, Giordano Bruno shocked the Church by proposing that “the excellence of God’ might be magnified and the greatness of his kingdom made manifest [if] he is glorified not in one, but in countless suns; not in a single earth, but in a thousand, I say, in an infinity of worlds.”
We’ve come a long way from this candle in the darkness. Today, the idea of the multiverse seems all around us in popular culture. Olaf Stapledon was the first to envision parallel worlds in fiction with his The Star Maker. Arthur C. Clarke considered it one of the finest works of science fiction ever written. In this profound novel, he imagined an infinite number of universes, each a branch from a previous one, “exfoliated from every moment of every temporal sequence in this cosmos.” Quantum mechanics predicts that a particle has multiple “states”, such as simultaneously passing through gate number one or gate number two. The particle travels in both “worlds” in superposition. It’s only after we observe this particle, that “chooses” which gate to pass. It’s as if our observations decide the fate of the particle. Now let’s extrapolate this paradigm out to the macroscale. Does this mean we have no free will? Do our actions result only from observations by another being—after the fact?
The Many-Worlds Interpretation would say no. The American physicist Hugh Everett first proposed the Many-Worlds Interpretation of quantum physics where every possibility embodied in Schrödinger’s probability waves is realized in one of a vast landscape of of an infinite number of universes. The quantum multiverse creates a new universe when a diversion in events occurs, known as a “branch-point”. When we decide on which gate to pass through (of our free will), we create a branch-point in our timeline. In this way, a new universe branches from the previous, creating a new world timeline.
Literature, television, and film continue to explore quixotic themes of parallel worlds or alternative histories. My favorite version of a parallel universe is The Wizard of Oz. Was it all just a dream, Dorothy? And let’s not forget more modern variations of this theme in the Star Trek episode The City on the Edge of Forever, the Borges story The Garden of Forking Paths, and the movie, Sliding Doors, and Philip K. Dick’s novel The Man in the High Castle. Collectively, these and many other works of popular culture have moved the concept of parallel realities into our zeitgeist and fueled public fascination with parallel worlds.
The multiverse envisioned in my science fiction series, Lost in the Multiverse, is what cosmologist Max Tegmark and string theorist Brian Greene call a “Level III” Multiverse. The parallel world setting for Mauna Kea Rising is one of many twin Earths born from branch-points created by time-travelers and their haphazard (or selfish) meddling with the world time-line.
In future articles, we’ll explore why we think parallel worlds exist. We’ll also search for evidence, or at least ways in which we can test this Many-Worlds Interpretation of quantum mechanics. And what if we could travel to these other worlds, then what might they look like?
For Further reading:
Brian Greene. The Hidden Reality. Knopf Doubleday Publishing Group, 2011.
John Gribbin. In Search of the Multiverse: Parallel Worlds, Hidden Dimensions, and the Ultimate Quest for the Frontiers of Reality. Turner Publishing Company. Kindle Edition.
Jorge Luis Borges, Collected Fictions, trans. Andrew Hurley, Allen Lane, 1998.
Michio Kaku. Parallel Worlds: A Journey Through Creation, Higher Dimensions, and the Future of the Cosmos. Knopf Doubleday Publishing Group, 2006.
M.W. Kelly. Mauna Kea Rising. Hokulei Press, 2019
Olaf Stapledon. Star Maker. Millennium Paperbacks, 1937.Edit”The
