Ghost of the Machine: Sounds in the Paranormal
Some of the things we encounter in our lives seem to be simply inexplicable, but our innate curiosity urges us to attempt to explain inexplicable events nonetheless. By experimenting and making educated guesses, scientists have learned that most of the phenomena we once considered unexplainable can actually be explained by using the laws of physics. One superstition that has stood the test of time is society’s beliefs in ghosts.
Nearly every culture believes in some kind of spirit that exists beyond the human dimension. Elves, spirits, djinns, ghosts – whatever you may call them, they have seemingly existed in human culture since the dawn of time. However, scientists at the National Physical Laboratory in England have reason to believe that we people haven’t really been seeing ghosts at all; rather, we have been sensing auditory distortions!
Normally, humans hear sounds that are above 20 Hertz, a frequency of sound. We can only hear sounds that are higher-pitched than 20 Hertz. Frequency is not to be confused with the intensity (more commonly, volume) of a sound, which is measured in decibels. Sounds with low frequencies cannot be heard, but our bodies can still sense them. If the intensity of a sound is high enough, in other words, if it’s “loud” enough, your body will feel it. Think about how a car with a big sound system shakes because of the bass. You don’t hear the music very well, but you can still feel the vibrations (and so can the car).
But what does being in the presence of infrasound have to do with feeling fear, anxiety, and nervousness? It may have something to do with natural sources of infrasound: volcanoes, earthquakes, tiger roars, and strong ocean waves. Our bodies may have evolved to detect the sounds that we cannot hear, and we may have evolved to fear these dangerous sounds.
Just like other seemingly unexplainable phenomena, ghost sightings have long perplexed scientists. But with the help of some simple monitoring equipment, scientists have been able to unravel some of the mystery that surround haunted houses. So next time you think your house is haunted you may want call an engineer, rather than a sprit medium.