Ghostbusters: 7 Scientific Facts To Make You Hate It Less

2. 'Real' Ghosts

Obviously, the ghosts in Ghostbusters are pretty difficult to put down to a trick of the light, but why do some many people in the real world claim to have encountered the supernatural? They can't all be mad and/or liars, so some think that there could be some real physical causes behind the apparitions (Hint: it's not the wandering souls of the restless dead).

As previously hinted, there are those who think that the presence of electromagnetic fields could be a cause rather than a symptom of paranormal experiences. Strong magnetic or electrical fields have been known to cause bright flashes of light to zoom across people's vision. As well as this, a strong magnetic field to the temporal lobe can cause people to sense a mysterious unseen presence and even have a religious experience. Someone has even made a God Helmet to prove it.

Aside from electromagnetism, a phenomenon known as infrasound has been put up as a possible explanation for alleged hauntings. As the name suggests, infrasound is a noise so low that it is below the register of human hearing. Despite this, you can still feel its effects, with a similar sense of a "mysterious presence", and it can even cause blurred grey shapes to move across your vision.

All this, coupled with confirmation bias and a healthy imagination, can explain a lot of hauntings - although the research is still inconclusive with regards to what in the name of sweet jesus the slimer is.