Buses jumping a 15 meter gap in a highway, as in Speed? No way. Humans plummeting 80 stories without a single broken bone (Spider-Man 3)? Uh-uh. What about Tom Cruise and Dougray Scott walking away from a 160-kilometer-per-hour midair motorcycle collision (Mission Impossible II)?
”Applying Newton’s second law, this collision would result in accelerations of around 200 g’s,” calculates Adam Weiner, a high school physics teacher, lecturer, and author of Don’t Try This at Home! The Physics of Hollywood Movies (Kaplan, 2007). ”150 g’s is usually fatal.”
Weiner is part of a small cottage industry of scientists and educators that includes James Kakalios (The Physics of Superheroes), Lawrence Krauss (The Physics of Star Trek), and Philip C. Plait (Bad Astronomy: Misconceptions and Misuses Revealed, From Astrology to the Moon Landing ”Hoax”), who delight in poking fun at the science-defying feats of action stars and superheroes.
On 6 August, Weiner spoke at ”When Worlds Collide: The Science of Movies,” a seminar at the Los Angeles headquarters of the Academy of Motion Picture Arts and Sciences sponsored by its Science and Technology Council. He asked the 1000 attendees who filled the theater, ”How many of you have seen a movie and wondered if that was physically possible?” Applause. ”How many have seen a movie and thought, ’That’s completely ridiculous.’?” Bigger applause. ”That’s what this talk is about!” he said, laughing.
”We all know Superman isn’t real, but when we watch a movie like The Core, where they’re portraying things that are seemingly scientific, they have a greater obligation to get it right,” Weiner said during a prepanel reception. ”For example, in The Core, they say, ’The frequency of seismic waves changes as it goes across an interface,’ when it’s actually not true. When a wave goes across an interface, the frequency is constant, but the wavelength changes. It wouldn’t hurt the plot to get that one right.”
Weiner acknowledged films that have gone out of their way to be scientifically accurate: 2001: A Space Odyssey (for its rotating space station to approximate gravity), Apollo 13 (which depicted weightlessness through parabolic flight and exquisitely counterbalanced platforms), and Titanic (for explaining how the added weight of flooding seawater exceeded the buoyant force, causing the ship to sink). So why does Hollywood so often get its science wrong?
”Usually, there’s no pressure to have films scientifically accurate—it’s more about art than science,” said stunt coordinator Dan Bradley, who served as second unit director for The Bourne Ultimatum. ”In my work I try to keep it feeling real, like paying attention to how fast things fall. But it’s about entertainment. What reality is to a movie audience has more to do with other movies they’ve seen than what real life is. That’s really the crux of the problem.”
”Much of my job as special effects supervisor is to violate the laws of physics to serve the film,” said Matt Sweeney, who has earned three technical achievement awards from the Academy. ”Take the example of an explosion in space. If an audience sees an explosion, they expect to hear a sound. They don’t realize there’s no sound in space. So you gotta have it; it’s art, not science.”