Fairy Tale Science

I have a six-year-old daughter, which means in the past few years I’ve been reintroduced to the wonderful world of fairy tales.

I’m as willing to suspend disbelief as the next guy--more so, probably, since I’m a reader and writer of fantasy--but I also have a scientific bent, and every once in a while I get to thinking about the scientific plausibility of these oft-told stories.

Apparently I’m not the only one. Chris Gorski, writing for the Inside Science News Service of the American Institute of Physics, recently decided to look at some magical moments from famous fairy tales and examine them as a scientist. Could they actually happen?

Gorski begins with Rapunzel, the Brothers Grimm heroine locked in a tower by a witch. Rapunzel’s two notable attributes are a lovely singing voice and extremely long blond hair. When a prince hears the former and comes calling, she tosses the latter out the window so that he might climb up to her.

As a kid, I remember thinking something along the lines of, “That’s gotta hurt,” and I’m sure my daughter would concur, considering the high ouch-per-minute rate my brushing of her hair generates each morning.

According to Gorski, one strand of hair can support about 3 1/2 ounces, “about the weight of two candy bars,” (an odd standard of measurement, but never mind). Dark hair is generally thicker and stronger than blonde hair.

Still, a typical blonde has about 140,000 hairs, so using the candy-bar standard, Rapunzel’s hair should be able to support 280,000 candy bars, or about 280 princes, the precise number depending on the number of candy bars the prince regularly ingests.

So far so good. But, as Gorski points out, while her hair might not break, it very well might rip out. Or she might suffer other painful injuries from all that weight on her head and neck.

Fortunately, physicists are standing by to help her out (although how they’re going to get up to her tower, I’m not sure). Nathan Harshman, Assistant Professor of Physics at American University in Washington, D.C., suggests she should tie her hair around something before lowering it. That object would then support the weight rather than her scalp.

Gorski next turns his attention to the Disney version of The Little Mermaid (now a Broadway musical!), in which Ariel exchanges her voice for a witch’s transformation of her into a human. She does it because she has fallen in love with a human prince, but since he can only recognize her by her beautiful singing voice, her muteness is a problem. (Don’t worry, it all gets sorted out in the end.)

Gorski says the witch wouldn’t necessarily have to use magic to silence Ariel’s voice. Recent research has shown that it is theoretically possible to create a sound shield, a material that would bend sound waves around walls and pillars so that they emerge on the other side as though the object had never been in their way. That means it is also possible to keep sound waves from emerging from an enclosed space--such as Ariel’s mouth--at all.

Ursula may not have been a witch at all: maybe she was just a talented physicist.

Finally, Gorski looks at the flying carpet of the Arabian Nights (and, to keep up the Disney theme, Aladdin. Rapunzel, by the way, does not exist in a Disney version that I’m aware of, but there is an amusing Barbie version...what? Why are you looking at me like that?).

Three scientists recently published a paper that shows that a carpet can indeed fly, if the air is vibrating at just the right frequency. Their work shows that small waves of air in repeated fast pulses could steer a small, thin carpet at a speed of around one foot per second.

The late Arthur C. Clarke famously declared that “Any sufficiently advanced technology is indistinguishable from magic.”

If that is true (and it clearly is), then the opposite must also be true: magic is indistinguishable from advanced technology.

Something I’ll make sure my six-year-old is aware of as we read and watch fairy tales.

I’m sure she’ll thank me for it.

These weekly columns on science appear in the Regina (Saskatchewan) Leader Post and Red Deer (Alberta) Advocate.  They are available for one-time publication or regular syndication to any interested newspapers, magazines or on-line publications.  E-mail me for details.