Not able to leap tall buildings, but he can sure make physics fun
The Physics of Superheroes, a new book by U prof James Kakalios, shows how comic books get science right--or, sometimes, hilariously wrong
By Deane Morrison
Published on September 16, 2005
Who can count the freshmen who arrive at college eager to learn but trembling in abject terror at the thought of encountering a science course? In his freshman physics seminar, James Kakalios found a way to break the fear-of-science barrier. He taught Newton's famous equation F=ma not as a dry explanation of how a force imparts acceleration to a mass, but as the inescapable principle behind the death of Spider-Man's girlfriend, Gwen Stacy (in the comic book, not the movies). His seminar, "Everything I Know of Science I Learned from Reading Comic Books," was a hit, and with the 2002 release of the first Spider-Man movie, Kakalios' class made him an instant celebrity of sorts.
"Assuming that Spidey's webbing catches her after she has fallen approximately 300 feet, Gwen's velocity turns out to be nearly 95 mph," he says. Unfortunately, Spidey's web slows her down almost instantaneously. "If it were a bungee cord, it would be different," says Kakalios. "You slow down gradually, so it doesn't take such a big force to come to rest."Now, everybody can get the benefit of Kakalios' wit and wisdom. He has put his ideas into a book, The Physics of Superheroes, which will be officially published September 29. Illustrated with panels from famous comics like Superman, The Flash, The Atom, and, of course, Spider-Man, the book opens with a foreword by Lawrence M. Krauss, author of The Physics of Star Trek. Is the book good? It's great--but don't take our word for it. Check out the starred Publisher's Weekly review at Amazon.com. Kakalios will give a multimedia talk based on his book at 7:30 p.m. Thursday, October 13, in Room 150 of the Physics Building. The event is sponsored by University Bookstores, which will carry the book. If you somehow missed the rash of news reports of Kakalios' seminar three years ago, you're probably wondering what did happen to Gwen Stacy and what Isaac Newton had to do with her. So a quick review: When the evil Green Goblin knocked Gwen off the George Washington Bridge, Spider-Man quickly cast out his web to stop her fall. He caught her leg just as she was about to plunge into the dark water. But when he hauled her up, he discovered to his horror that she was dead. The villain said she had died from "the fall" and that Spider-Man's web had nothing to do with it. But Kakalios has a different explanation. "Assuming that Spidey's webbing catches her after she has fallen approximately 300 feet, Gwen's velocity turns out to be nearly 95 mph," he says. "In order to change [her] motion from 95 mph to zero m.p.h., an external force is required, supplied by Spider-Man's webbing." Starting with the equation F=ma, Kakalios shows that the faster Gwen is slowed down, the larger the force that must be applied to her body. Unfortunately, Spidey's web slows her down almost instantaneously; this exerts a tremendous force, snapping her neck. (This is confirmed by the fact that the comic book panel where the web snags her contains the notation "SNAP!" in large letters.) "If it were a bungee cord, it would be different," says Kakalios. "You slow down gradually, so it doesn't take such a big force to come to rest." The same principle holds for car airbags, which, for all their speed of inflation, deform under contact and stop your forward motion much more slowly than a steering wheel or windshield would. How about Superman's 1961 trip through time to save Atlantis from sinking? He accomplishes that, and on the return trip to the 20th century he also saves the lives of Nathan Hale, Abraham Lincoln, and George Custer. Returning to Earth in 1961, Superman is dismayed to find that history hadn't been changed by his actions. So he retraces his steps back through time and finds out that, as he was time-traveling, he inadvertently created--and slipped into--an alternate universe. Revisiting that universe, he finds he has indeed changed its history. A crazy idea? Maybe not. Quantum theorists have just recently hypothesized that travel through time must necessarily involve transport to alternate, parallel universes. The above are two examples of comic books getting physics right. For examples of mistakes, read the chapter "Me Am Bizarro! Superhero Bloopers." One concerns Spider-Man foe Doctor Octopus, who would certainly tip over whenever he raised and moved the heavy robotic arms fused to his body. Another glaring error: A panel depicting an early stage in the career of The Atom implies that "in the mid-1960s, physics professors typically drove Cadillac convertibles." Kakalios doesn't need any formulas to know that isn't true.