April 5, 2006

Superpower science

By Jesse Semko
jsemko@uwo.ca

Indeed, Superman's super strength and speed, not to mention Professor X's ability to read and control people's thoughts, seem like abilities that are only possible in a comic book, or a Hollywood flick.

Or so we think.

Enter James Kakalios, a man whose scientific genius matches that of Superman's arch nemesis, Lex Luthor.

A professor in the school of physics and astronomy at the University of Minnesota, Kakalios has a special understanding of the science behind superpowers. He's the author of a book on the subject, The Physics of Superheroes, and teaches a class that uses superheroes to exemplify principles in physics.

Take Superman's fabled strength and ability to leap over a tall building in a single bound.

According to Kakalios, this can be explained by understanding the gravity on Krypton, Superman's home planet.

Courtesy of James Kakalios

James Kakalios teaches a freshman seminar at the University of Minnesota titled "Everything I needed to know about physics I learned from comic books."

"Just as our muscles and skeleton are adapted to earth's gravity … Superman's body must be adapted to the much larger gravity of Krypton to be able to leap tall buildings," says Kakalios, during a phone interview from Minneapolis.

But how strong would the gravity on Krypton need to be to strengthen Superman's muscles enough that he could make such a leap?

Well, to figure that out Kakalios says you need to know a number of factors, such as Superman's weight, the height of the building and the force needed to make the jump.

Most of this information is provided in the comic, which has Superman's weight on Earth at 100 kg and pins his jumping abilities at being able to clear a building roughly 30 to 40 stories in height.

Given these variables Kakalios says that Superman would have to go from zero to 225 km/h in the time it would take you to make the leap, probably a quarter of a second.

"By knowing this and that he can leap a tall building in a single bound, we can figure out that the minimum excess gravity on Krypton would have to be roughly 15 times larger than that on Earth."

However, a problem still remains.

A look at Newton's law of gravitation and realize how hard it is to explain how a planet with that much gravity could exist, Kakalios says. But there is still one more trick you can play.

"If you take a planet and put some extra super-dense material, like a neutron star, in its centre, you could boost the gravity to 15 times that of Earth."

According to Superman's origin, his parents sent him to Earth because Krypton was about to explode. Kakalios says this works with the idea of having a neutron star in the centre of the planet.

"Now you understand why Krypton exploded because such an immense gravity (of a neutron star) would create these huge pressures and strains."

Similar to Superman, Kakalios says the X-men characters can also be used to demonstrate certain principles in physics.

"A lot of their powers are kind of goofy. But what I do in my class and with my book is grant the characters a onetime exemption from the laws of nature to see how anything else would work."

For instance, Magneto, the evil mutant master of magnetism, is able to levitate himself and others because water molecules are diametric, Kakalios says.

This is another way of saying that water molecules line up in the opposite direction of a magnetic field, so if two magnetic fields at equal strength are applied it will cause the water molecules to be repelled equally in the opposite direction.

This principle is well documented, Kakalios says. If you Google "diametric levitation frog" you should be able to find a movie of a frog, in a very large magnetic field, being levitated. And this is similar to how Magneto's powers must work.

"People, frogs and other things are made mostly of water. So when you apply a very strong magnetic field, the water molecules align, oppose the magnetic field and that repulsion of the magnetic field can be larger than the gravity holding you down on the ground."

"This principle that Magneto employs is perfectly reasonable."

But how he actually generates those fields remains a mystery, Kakalios says.

Kakalios also has an explanation for the powers of Professor X, the leader of the X-men.

Professor X's mutant powers include the ability to read people's minds and control their thoughts. Kakalios thinks this could be explained by understanding the beautiful symmetry that is electromagnetic radiation.

Electromagnetic radiation includes radio waves, X-rays, gamma rays, microwaves, infrared light, visible light and ultra-violet light. All electromagnetic radiation is interconnected and can be explained by alternating and oscillating electromagnetic fields.

"If you have any electro current that is changing its direction or magnitude it will generate a changing electric field, which in turn creates a changing magnetic field, which creates a changing electric field which will create an electromagnetic wave."

A person's brain works in a similar way, Kakalios says.

"Inside your brain you certainly have changing electric currents," he says. They may not be currents of electrons, they're currents of calcium or sodium ions, but they're currents nonetheless. And they emit extremely weak electromagnetic waves.

"By weak, I mean extremely weak — of the order of a billion times smaller than radio waves."

So, presumably, Professor X's miracle exemption from the laws of nature is that he has a tiny piece of his brain that is a billion times more sensitive to this type of radiation than normal, Kakalios says.

"It is entirely plausible that if you grant this one obviously impossible thing that Professor X could then send and receive electromagnetic waves that are far too weak to be detected by any other type of system."

It is also possible that he could somehow infer from the electromagnetic signals that someone is generating what they are actually thinking. Or perhaps control what their emotions are by sending out other signals that would short circuit what is going on inside their head, Kakalios adds.

Of course, Kakalios says this ability would disappear with distance, which explains why the comics they realistically portray Professor X as needing Cerebral, a machine that boosts his powers over great distances.

According to Robert Weinberg, co-author of the Science of Superheroes and the Science of Supervillains, machines like Cerebral may someday give people abilities that could mimic the powers of some superheroes.

"Man is inventive. Almost any power we can come up with in a comic book we can invent," Weinberg says, during a phone interview from Chicago.

For instance, optical camouflage may someday give people the ability to mimic the powers of Mystique, an evil mutant who can change her appearance.

"Optical camouflage is pretty cool," Weinberg says. "It enables you to be a chameleon and blend into the scenery."

The only problem is that right now it's still in the experimental stage which means it would be used more to help someone blend into their surroundings, rather than give them a new appearance, he says.

According to Weinberg, optical camouflage works by covering your entire body with mini scanners that take pictures of whatever is behind you and then flashes that same picture in front of you.

"It's kind of what they do with the James Bond car in the last James Bond movie."

While James Bond was driving the car, the car was scanning the ice and mountains around it and projecting those images onto the other side of the vehicle so you could never see it, he says.

Right now, the technology isn't really being pushed to its potential. But some day that will change, he adds.

"It will be really interesting when it is developed commercially."

Maybe then, people will have powers that would even make some mutants turn green with envy.