The Science of Monsters

What would it take for a person to actually fly on a broomstick? To understand flight, we need to understand Newton’s laws of motion. First, an object in motion tends to stay in motion or an object at rest tends to stay at rest. In order to get in the air, the witch would need to create thrust. The second law of motion states that the force gravity applies to the broomstick is equal to the mass of the broomstick, multiplied by the gravitational acceleration. The third law says that for every action there is an opposite and equal reaction. The amount of force created by magic to propel the broomstick forward will then, in turn, produce that much thrust to keep the broom in motion.

In several witch movies people are possessed by witches. What would the scientific explanation be for witches possessing people? The afflicted share certain unusual behaviors such as convulsions, fainting, changes in vocal and facial structure, and the loss of personality or memory. Before we had knowledge of conditions that could reasonably cause such behavior, these symptoms would be viewed as sinister or unnatural, leading to mass hysteria and public witch hunts such as the Salem Witch Trials. Hundreds of years later, though, scientists have suggested several explanations for these symptoms, the first of which is ergot poisoning or ergotism. Caused by the ingestion of fungi belonging to the genus Claviceps, it produces hallucinatory effects in the afflicted and can cause victims to suffer from vertigo, crawling sensations on the skin, extreme tingling, headaches, hallucinations, and seizure-like muscle contractions. Rye bread was a dietary staple in the colonies at the time, and historians have recognized that New England was unusually cool from 1690 through 1692. These were the perfect cool, damp conditions for the fungi to grow. Another medical explanation for unnusual behavior prominent during the Salem Witch Trials was an epidemic of bird-borne encephalitis lethargica. This is an inflammation of the brain spread by both insects and birds. Symptoms include fever, headaches, lethargy, double vision, abnormal eye movements, neck rigidity, behavioral changes, and tremors. Several girls suffered from these symptoms, and doctors at the time concluded that they suffered from being possessed by witchcraft.

Another power witches are said to possess is controlling things with their eyes or shooting lasers out of them. This power was seen in Roald Dahl’s The Witches (1990). To understand the scientific basis for this, we interviewed laser scientist Olivia Koski.

Meg:“How did you get interested in lasers?”

Olivia Koski: “After college I got a job at a small research company that studies laser radar. I loved every aspect of it—doing these tabletop experiments every day, setting up optical systems, shaping light at your whim. It was so much fun to work in the lab. Probably the moment I became hooked was when I built my first laser from scratch. Lasers require very careful alignment, and it’s often an all-or-nothing thing in terms of getting an output. You have to line up these mirrors in a laser cavity perfectly, and line up the energy source for the laser perfectly. Everything has to be just right. It was very frustrating the first time I built a laser. It didn’t work for a long time. But I hung in there, and the first time I got ‘first light’ and created a laser beam was a very satisfying experience.”

Kelly:“What’s the coolest thing you got to do in relation to laser technology?”

Olivia Koski: “The lasers I was working with were very powerful. You had to be very careful or you could cause some serious injuries. I’m not going to lie and say I never accidentally burned a component or two. The smell of burning plastic was usually a signal you should cut system power immediately. Or make a slight tweak to realign the beam if you’re feeling brave. I didn’t do this, but I heard of some folks having fun dropping frozen hot dogs in a beam path to slice them in two.”

Meg:“How close are we to being able to shoot lasers out of our eyes?”