Ghostbusting

I enjoyed the new Ghostbusters movie, and it got me thinking about how one traps a ghost. There is the candle and glass jar method, which I doubt really works. If a ghost passes through solid walls, it’s unclear why glass would physically trap it. Anyway, I am not steeped in Ghostbusters lore. I did watch and enjoy the original movie, but didn’t think about the gobbledygook science. I also vaguely remember a very old computer game thirty years ago based on the original movie.

In the new movie, at least, proton packs supply the energy for the bright energy streams used to encircle or punch ghosts. Protons could certainly be a fusion source; they might also constitute the energy stream although that is likely to do serious damage to ordinary matter. The mechanics of the traps aren’t really explained in the movie, although I may not have caught speedier parts of the conversation.

Fundamentally, how you trap a ghost depends on what constitutes a ghost. In a post last Halloween I speculated that they could be related to neutrinos (also dubbed “ghost” particles), and thus hardly interact with ordinary matter. In the Harry Potter series, the ghosts can certainly pass through walls and float unhindered by gravity. At the Deathday feast, ghosts try to interact with the foulest smelling putrid food to glimpse a “taste” of the material. Nearly Headless Nick does get knocked out by the basilisk, although being already dead he does not die a second time. This implies at least very weak interaction with ordinary matter – certainly with the airwaves since ghosts speak audibly.

Another possibility is that ghosts are an energy manifestation related to electromagnetic (EM) radiation. In this case, there are many ways one could interact with them. You could use an EM pulse as a ghost bomb, and you can certainly find ways to control and trap EM and thus make weapons that fight and trap ghosts. Optical traps are not uncommon in today’s science. You could certainly construct detectors; I think in Ghostbusters language this is a PKE or psychokinetic energy meter. What exactly is psychokinetic energy? Unclear.

In the movie, ghosts do find ways to interact with ordinary matter in a more substantial way. The first example is from sliming (and Slimer gets a cool cameo in the new movie). Ectoplasm (or “outer goo”) has a scientific meaning, but the movie taps into an older use of the term whereby charlatans holding séances would use it as a sign of a ghostly presence. Why goo? Couldn’t they have used something cleaner? I don’t know. In any case, making slime is a standard demo for elementary school kids and the chemistry is quite straightforward (with many YouTube videos in this day and age). It’s mainly cross-linked polymeric material with a certain consistency – the gooey kind. If the Ghostbusters team had a chemist, maybe the ectoplasm could be analyzed and we would have a better idea what constitutes ghosts.

Another method in the movie is via possession of a human. Now if ghosts were EM energy, and one makes a far-fetched connection with electric conduction through the nervous system, maybe that’s the physical connection in possession. Alternatively, the psycho part of PKE lodges itself in the brain and then controls the rest of the motor system. Interestingly, ghosts can also possess inanimate objects such as balloons and mannequins. I’m not sure how to explain that, but I suppose I can just sit back and enjoy watching the movie mayhem. Science gives way to entertainment.

The ghosts in the movie, except for the malevolent one in control of the others, don’t seem to have much of a personality – they’re more like zombies. Not much of the psyche in the psycho. This is in contrast to the ghosts at Hogwarts, all of whom seem to have retained their psyche and memories. Now that’s an interesting idea – can the psyche and memories be disembodied? Is there a ghost in the machine? But perhaps the embodiment simply takes a different form, be it neutrino-like particles, an EM network, or loading your mental state into a computer as seen in sci-fi.

I don’t remember much of the old movie, but one that made an impression that I still remember is the ZUUL building. I can identify it easily in any subsequent movie unrelated to ghosts