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How to Be a Better Ghost Hunter

Ghost hunting may look like science, but the way in which technology is misused is the scariest part of the hunt.

It was an honour to speak to a ghost. He looked quite normal and even knew how to operate a computer. Truth be told, he wasn’t a real ghost, but some people thought he was.

“It was a whole thing in Gettysburg, Pennsylvania,” he told me over Zoom. His name is Kenny Biddle and, at the time of the story, he was a ghost investigator. “I was at a spot with a bunch of ghost hunters, and there were other ghost hunters coming toward us, and I kinda came out of the woods and screamed at them to go away. And that became a ghost story.” They thought Biddle was a ghost. He heard them telling the story at a conference the next day, and even though he told them it had been him and gave them details about the encounter, they wouldn’t listen. Kenny Biddle had become a campfire legend.

“That was more or less my turning point. Something’s wrong with what I’m doing here. How can this happen?”

Our desire to communicate with the dead led to the birth of paranormal research and spiritualism in the 1800s. Now, ghost hunters have traded the embroideries and candlesticks of the Victorian era for technology. Television viewers seem to have a hunger for paranormal investigations that feel scientific: Ghost Hunters, which features members of The Atlantic Paranormal Society, has aired 251 episodes and 12 specials, while Zak Bagans’ Ghost Adventures clocks in at 231 episodes, 49 specials, multiple spin-offs, and a book, Ghost-Hunting for Dummies, which suspiciously features many passages that look plagiarized.

Millennials may be more familiar with BuzzFeed’s runaway success, Unsolved Supernatural, in which believer Ryan Bergara and skeptic Shane Madej explore creepy buildings with a host of sciency-looking instruments. They have now taken their approach to Watcher’s Ghost Files, where the gadgets are even more expensive.

But as these superstar ghost investigators and the local hobbyists they inspire wave around fancy equipment in dark rooms, are they actually engaging in science or merely playing pretend?

As seen on TV

Every ghost hunter worth their salt will carry around an electromagnetic field (EMF) metre. It is used in the belief that ghosts give off, interact with, or even manipulate electromagnetic fields, and that an EMF detector that lights up might indicate the presence of spirits.

Kenny Biddle, the former credulous ghost hunter, is now an investigator with an interest in carefully testing paranormal claims, and he often writes about his experiences in Skeptical Inquirer magazine. “I’ve literally seen ghost hunters,” he told me, “at a wall, right next to a light switch, and had [their EMF metre] spiking, and they’re like, ‘Look! There’s nothing around here that can make this go off.’” Of course, in a world ever more reliant on electricity, we are surrounded by electromagnetic fields and it is the duty of ghost hunters to rule out normal explanations for their readings. But in Biddle’s experience, they typically do a very cursory look around to rule out anything obvious before concluding that it could be ghosts. Moreover, the devices they can afford are single-axis EMF metres, which need to be rotated around all three axes in every single spot before taking a reading. Good luck finding a ghost hunter who does that.

There is, of course, no reason to believe that ghosts, if they exist, would be able to interact with electromagnetic fields in their disembodied states. That dubious idea might be traced back to a famous movie. “I believe the idea came from Ghostbusters,” Biddle speculated. Its characters used similar looking detectors, and EMF metres became popular in the late 1980s, early 1990s among ghost hunting groups, a few years after the release of the movie. “Ghost hunters have a habit of just adapting any kind of technology, especially if it beeps, if it makes noise or lights up, they want it! They don’t know how it’s supposed to work. All they know is that they saw it on TV and it looked cool.”

EMF metres are real devices with a real purpose. I chatted with Dany Plouffe, a teacher at Collège Bois-de-Boulogne with a Ph.D. in physics who has long given talks about the misuse of technology by ghost seekers. “If ghosts truly emitted electromagnetic fields, Hydro-Québec [our public utility for electricity power] would know about it, because they use these metres to detect leaks.” And before you ask, yes, he did inquire to an employee of Hydro-Québec if they had ever detected ghosts. The answer was no.

Putting aside the EMF metre, ghost hunters on television can sometimes be seen talking to a flashlight. It can be quite freaky seeing a flashlight flicker on and off as an investigator, who is standing in a dark, empty room, questions unseen spirits. “Did you die violently?” they might ask. “If you did, turn this flashlight on.” After a long, dreadful silence, the flashlight comes to life, often accompanied by a musical stinger added in the editing room. But the creepy communication on display boils down to heat.

It has to be done with a Maglite equipped with a xenon bulb. Crucially, this is a model that is turned on or off by screwing its head out or in, respectively. Leave the head somewhere in the middle and vibrations may cause it to turn on or off, giving the impression of communicating with the great beyond. But even without vibrations, the light will cycle through its on and off states if its head remains on the cusp of its on position. As this video demonstrates, the plastic lens in front of the bulb heats up by 13 degrees Celsius when the bulb is on. This causes the plastic to expand, which results in the flashlight head turning by 2.6 degrees, which puts pressure on the metal spring at the bottom of the lamp, resulting in the electrical contact being broken. The bulb goes off. The plastic reflector starts to contract back. Pressure on the spring is relieved, and contact is re-established. If you happen to be asking questions while this Maglite cycles on and off, you’ll be given the impression that otherworldly forces are using a very primitive Morse code.

Looking for visual clues to a haunting is one thing, but what if you could hear ghosts? Enter the spirit box, a device that quickly scans through radio frequencies sequentially without stopping when it lands on a radio station. The ghost hunter asks a question and listens to the bursts of white noise occasionally interrupted by a stray word from a radio announcer. This is seen as the ghost manipulating the airwaves to communicate. Kenny Biddle and I held an impromptu demonstration while we were chatting, showing how anything coming out of this can be infused with meaning. He shouted random words that might be heard over the spirit box: “Chair! Hair! Red!” My reaction? “This is how she died!” I could imagine a woman with red hair hanging herself by kicking the chair from under her. Any sound bite from a radio station heard through the spirit box can be used to feed an imaginary story.

To up the ante, Biddle built a Faraday cage, a box that blocks electromagnetic waves like radio signals, and he brings it to ghost investigations when he knows a spirit box will be used. Inside the Faraday cage, the spirit box cannot receive the signals broadcast by radio stations. If a ghost can truly manipulate electromagnetic fields, it should be able to enter the cage and generate a signal. So far, Biddle reports, that hasn’t happened.

As Plouffe pointed out to me, if I were asked to generate an AM or FM radio signal right here on the spot, would I be able to? The answer is no. So how is it that I would gain this knowledge upon dying?

Undeterred, ghost hunters often refuse to strengthen their methodology, simply buying more expensive equipment and inviting murky signals in.

Anomaly hunters

On Ghost Files, we witness an array of techno gadgets that act as false positive traps.

There’s the REM Pod, a stout cylinder with coloured lights that are said to be triggered by ghosts. The only problem is that it’s actually a repurposed musical instrument, a Junior Theremin. The theremin, whose spooky sound has graced science fiction movies like The Day the Earth Stood Still, has two antennas, which create audible electromagnetic fields whose pitch and volume can be altered by the movement of the player’s hands in front of the instrument. The Junior Theremin is meant to be a cool science project for kids to put together. It’s not a ghost detector.

There’s the structured light sensor or SLS camera, which is a repurposed Microsoft Xbox Kinect, a motion sensor that is used to detect a video game player’s body in space so that they don’t need to use a handheld controller. Hooked up to a monitor, it will show crude stick figures in real time where it detects bodies, except that it was never meant to be used in rooms with furniture and equipment. Looking at the end of a sofa, the sensor gets confused and can assign a stick figure to it, making it look like there is a human-shaped presence in the room where there isn’t. Given that it uses infrared light to detect these invisible bodies, aiming an infrared camera at the same spot should also reveal the ghost, yet it never does.

And then there’s the Ovilus, a square monitor with two short antennas sticking out. Despite its makers clarifying that it is sold “as an entertainment device only,” its high-tech status is too much for wealthier ghost hunters to resist. The Ovilus picks up on electromagnetic energy, assigns a number to it, and this number corresponds to a word in the dictionary the device is programmed with. An artificial voice speaks out the word. It is thus a more elaborate and, at USD 549, more costly version of the spirit box.

Ghost hunters don’t typically hunt ghosts; they hunt anomalies. They generate as much noise as possible with the instruments they deploy on location, then comb through this noise for any signal. The signal is never clearly coming from the dead, but the ghost hunters use motivated reasoning and our brain’s ability to see patterns even where there are none to fit the murky signal to a narrative. Investigations are almost always carried out in the dark, which invites even more noise. An important point Dany Plouffe made to me is that ghosts, who no longer have physical eyes, are said to be averse to visible light, but the infrared spectrum is fine with them. Ghost hunters use infrared cameras all the time. Why does light in the visible spectrum scare off eyeless spirits while light with a slightly longer wavelength—infrared—fails to disturb them?

The manner in which the search for ghosts is conducted has not changed significantly since its inception. The instruments may be more expensive, but the way in which they are used is the same. “It’s not a progression,” Kenny Biddle noted, “it’s more like a sidestep. Honestly, there’s no progression from the late 1800s. Nothing.” The lack of progress is a hallmark of pseudosciences.

Most ghost hunters do mean well, both Biddle and Plouffe remarked, but there are grifters in their midst. Plouffe showed me a clip from a popular ghost hunting show in which an investigator is seen switching their EMF metre on with their finger to get the lights to turn on in response to a question. The investigator probably did not realize the camera was on him at the time: it was shot in the dark with an infrared camera. Plouffe was also asked to analyze sound recordings made by ghost hunters where the sound wave, once looked at using the right software, clearly showed editing. It’s easy to make a ghost say something when you insert a fake clip into the actual recording.

Ghost hunting does not need to stay in the self-deceptive realm of the pseudosciences, however. It can be done more scientifically. Plouffe invites ghost seekers to bring in building experts, for example. Weird noises and anomalous EMF readings can usually be explained away by people who understand how houses are built.

For Biddle, there are many aspects of ghost hunting that could be tightened. Log your data. Collect base readings in different conditions: when the presumed haunted house is empty versus full, during the day versus at night, in summer versus winter. If you’re going to measure electromagnetic fields (for some reason), get a TriField metre, which is more precise. When asking questions to potential ghosts, ask the same question over and over again and see if you keep getting the same answer.

And stop watching ghost shows! “That’s not science at all,” Biddle says. He recommends books like Benjamin Radford’s Investigating Ghosts: The Scientific Search for Spirits, Sharon Hill’s Scientifical Americans: The Culture of Amateur Paranormal Researchers, and any book by Joe Nickell.

As for instruments, sometimes the simplest thing can make the biggest difference. To see if the floor is even, Kenny Biddle might bring a level. “A spirit level,” he says before we start laughing. “That’s what it’s called! So many ghost hunters have no idea that it’s actually called a spirit level.”

Clearly, they need to do their homework.

Take-home message:
- The idea that ghosts, if they exist, can interact with or generate electromagnetic fields is not based in science
- Ghost hunters frequently repurpose devices and misuse them when looking for ghosts, generating a lot of noise to search for a signal that can be interpreted to fit a story
- The lack of progress made by ghost hunters, who use more expensive equipment without making their methods more rigorous, is a classic sign of a pseudoscienc


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