“Doctor Strange in the Multiverse of Madness,” theatrically released in early May, develops the concept of the multiverse in the Marvel Cinematic Universe (MCU) by establishing how different universes interact with each other. As with most good science fiction, it represents a combination of both “fiction” and “science” — in this case, quantum physics.
In quantum physics, multiverse hypotheses suggest that Earth’s universe may be one of many. Dr. Tony Crider, an astrophysics professor from Elon University, clarifies that “there’s no evidence of a multiverse yet,” only untested models.
Multiple hypotheses about parallel universes exist, but Dr. Crider narrows it down to the three most prevalent, distinct and different models: Bubble Universes, Extra Dimensions and Many-Worlds models. The Many-Worlds model relates to the MCU most directly.
In classical physics, existing laws allow scientists to predict the outcome of certain situations. When a ball is thrown into the air with a certain amount of force, scientists can calculate how high it will go and when it will come back down.
However, this predictability does not work for the smaller scale of quantum physics. On a quantum level, each action can have many outcomes, and each potential outcome has a certain probability of happening.
Dr. Chris Richardson, another astrophysics professor at Elon University, explains that, in the Many-Worlds model, “All of these different possible outcomes do occur, but only one of them occurs in our universe. All of the other possible outcomes occur in different universes.”
In the Many-Worlds model, the universe diverges every time a decision is made, so that there are an infinite number of possible universes that can differ based on the smallest detail. For example, if a car has the option to turn left or right at an intersection, the Many Worlds model holds that the car turns in both directions — a divergence into two different universes.
These universes can differ in the slightest way, such as the subtle difference in the direction that the car is turning, but eventually, over time, they can grow to become more distinct from one another.
In “Doctor Strange in the Multiverse of Madness,” there’s a Doctor Strange in every universe, all variants of Stephen Strange played by Benedict Cumberbatch. The existence of the different versions of superhero Doctor Strange establishes that the car accident that caused Doctor Strange’s injury and subsequent journey to study the mystic arts likely occurred in each universe.
Therefore, the divergence between those universes transpired after the accident at different points in time. Understanding the physics behind “Doctor Strange in the Multiverse of Madness” is not paramount, but establishing that concepts in science fiction, such as the multiverse in the MCU, are based on genuine science promotes an interest in science and makes the story more believable. By making the plot more credible, the film itself becomes more incredible.
“The Martian,” a film released in 2015 based on a book of the same name, follows the journey and trials of a human mission on Mars. Though the trip itself is aspirational and fictional, the film pulls from some scientific discoveries and hypotheses. Mark Watney can grow crops in the soil on Mars, which aligns with scientific evidence that the soil on Mars may even be more suitable for crops than Earth’s soil. Using human waste as fertilizer would make Watney’s crops richer, which is also seen in the film.
Other science fiction evokes scientific discoveries as well. Prior to the Moon landing in 1969, multiple science fiction narratives and films from decades earlier imagined journeys to the Moon. The silent film “Frau im Mond” (“Woman in the Moon”) from 1929 presented what’s considered the first relatively well-known science fiction narrative that introduced traveling to the Moon by rocket.
The film was predated by “Le Voyage Dans la Lune” (“A Trip to the Moon”) in 1902, which was seen by a smaller audience and was inspired by novels by both Jules Verne and H.G. Wells. Science fiction often creatively imagines what could be possible with some scientific evidence.
“Frau im Mond” and “Le Voyage Dans la Lune” prove that the fantasy of going to the Moon began decades before the space race. At the time, it seemed impossible to land humans on the Moon, but in 1961, President John F. Kennedy announced the United States’ ambition to send an American to Earth’s natural satellite.
With “The Martian,” the writers imagined a future with the resources for space travel to Mars that is safe for humans. The imagined future is growing closer, as some scientists believe humans may land on Mars as early as the 2030s. Earlier this year, Elon Musk had considered a mission to Mars in 2029.
Yet, while based on scientific theory, science fiction remains just that: fiction. Science fiction stories are often illogical and depart from science to enhance the plot. The ability to walk between parallel universes that America Chavez (Xochitl Gomez) shows off in “Doctor Strange in the Multiverse of Madness” is improbable, if not impossible.
Dr. Crider contradicts the logic behind the Sacred Timeline from “Loki,” by explaining that the Copernican Theory establishes that “every time that you think that you’re special, you should recognize that you’re not.” Despite the relations between the multiverse as seen in “Doctor Strange in the Multiverse of Madness” and the Many-Worlds theory, other MCU films and television shows appear less able to follow the model.
“What If” presents the closest resemblance to the Many-Worlds model, as one slight alteration in the timeline creates an entirely different world and story, but both “Loki” and “Spider-Man: No Way Home” have the same characters from different universes looking physically different.
How does Peter Parker exist in different universes with the same relatives but look completely different and age at a different rate? How does Loki’s character have a crocodile variant?
Following the Many Worlds theory, all variants of Parker and all variants of Loki should appear in the same form, but the differences in appearance establish that science fiction is first and foremost fiction. Even with a scientific basis, the writers create a narrative that is marketable to an audience over one that follows scientific theories.
The multiverse that exists in “Doctor Strange in the Multiverse of Madness” and in the MCU relates to actual scientific models about parallel universes, but the films and television shows distance themselves from science by presenting narratives that align more with the writers’ visions and the audience’s desires. The best science fiction is often linked to actual scientific theories because science provides ideas that writers can enhance to create stories that people want to read and see.
Where will the MCU go next? The MCU’s next steps are anyone’s guess as audiences cannot predict the direction of the future of the MCU any more than scientists can predict the future of multiverse modeling. Fans can only be sure that the multiverse will continue to play a role in future MCU films.