Poltergeist denotes a spirit or ghost that manifests itself by moving and influencing objects.
- Mischievous spirits
A pamphlet printed in London in 1698 by Mr. Ricard Chamberlain provides an account of a poltergeist-type haunting that had occurred some years before. Two copies of the pamphlet exist in the British Museum called: "Lithobolia, or stone throwing Devil. Being an Exact and True account (by way of Journal) of the various actions of infernal Spirits or (Devils Incarnate) Witches or both: and the great Disturbance and Amazement they gave to George Walton's family at a place called Great Island in the province of New Hampshire in New England, chiefly in throwing about (by an Invisible hand) Stones, Bricks, and Brick-Bats of all sizes, with several other things, as Hammers, Mauls, Iron-Crows, Spits, and other Utensils, as came into their Hellish minds, and this for space of a quarter of a year...."
- Poltergeist activity originates with agents
Poltergeist activity tends to occur around a single person called an agent or a focus. Foci are often, but not limited to, pubescent children. Almost seventy years of research by the Rhine Research Center in Raleigh-Durham, North Carolina, has led to the hypothesis among parapsychologists that the "poltergeist effect" is a form of psychokinesis generated by a living human mind (that of the agent). According to researchers at the Rhine Center, the "poltergeist effect" is the outward manifestation of psychological trauma.
- Separate existences
Poltergeists might simply exist, like the "elementals" described by oculists. Another version posits that poltergeists originate after a person dies in a powerful rage at the time of death. According to yet another opinion, ghosts and poltergeists are "recordings." When there is a powerful emotion, sometimes at death and sometimes not, a recording is believed to be "embedded" in a place or, somehow, in the "fabric of time" itself. This recording will continue to play over and over again until the energy embedded disperses. However some poltergeists have had the ability to articulate themselves and to have distinct personalities, which suggests some sort of self-awareness and intent. Practitioners of astral projection have reported the existence of unfriendly astral life forms, which Robert Bruce called "negs" (whom we might also identify with elementals). If they exist, these may well have the ability to affect the physical world.
- Caused by physical forces
Some scientists and skeptics propose that all poltergeist activity that they can't trace to fraud has a physical explanation such as static electricity, electromagnetic fields, ultra-, and infra sound and/or ionized air. In some cases, such as the Rosenheim poltergeist case, the physicist F. Karger from the Max-Planck-Institute für Plasmaphysik and G. Zicha from the Technical University of Munich found none of these effects present and psi proponents claim that no evidence of fraud was ever found, even after a sustained investigation from the police force and CID, though criminologist Herbert Schäfer quotes an unnamed detective watching the agent pushing a lamp when she thought nobody was looking. However, whether this is true or not, police officers did sign statements that they had witnessed the phenomena. Other aspects of the the case were hard to explain: The time service was rung hundreds of times, with a frequency impossible with the mechanical dialing phones of 1967. The municipal authority disconnected the office from the mains supply and hooked it up to a dedicated generator hoping to stabilize the current. But surges in current and voltage still occurred with no detectable cause according to Zicha and Karger. John Hutchinson has claimed that he has created poltergeist effects in his laboratory. Also worth noting is that scientist David Turner proposes that poltergeists and ball lightning may be linked phenomena.Some scientists go as far as calling them pseudo-psychic phenomena and claim that under some circumstances they are caused by obscure physical effects. Parapsychologists William G. Roll and Dean Radin, physicist Hal Puthoff and head of electrical engineering at Duke University who specializes in electromagnetic field phenomena, claim that poltergeist phenomena [the movement of objects at least] could be caused by anomalies in the zero-point field, this is outlined in the above article and in Roll's book Unleashed and mention is made of it in a chapter of Dean Radin's book Entangled Minds. The basic theory is that poltergeist movements are repulsive versions of the casimir effect that can put pressures on objects. Thus, anomalies in this field could conceivably move objects. This theory has also been mentioned in the current book on paranormal phenomena Science by Marie D. Jones.The theory is not complete, however, because it accounts for the movement of objects but not for the strange voices, seeming personality, and strange electrical effects displayed in some cases.
- Self-delusion and hoaxes
Skeptics think that the phenomena are hoaxes perpetrated by the agent. Indeed, some poltergeist agents have been caught by investigators in the act of throwing objects. A few of them later confessed to faking. Skeptics maintain that parapsychologists are especially easy to fool when they think that many occurrences are real and discount the hoax hypothesis from the outset. Even after witnessing first hand an agent throwing objects, psi-believing parapsychologists rationalize the fact away by assuming that the agents are only cheating when caught cheating, and when you do not catch them, the phenomenon is genuine. One reason given is that the agents often fake phenomena when the investigation coincides with a period of time where there appears to be little or no 'genuine' phenomena occurring. Another stated reason is that some of the phenomena witnessed would be hard to fake, even for magicians when under the watch of many people, let alone untrained children and non-magicians.
William Roll, Hans Bender, and Harry Price are perhaps three of the most famous poltergeist investigators in the annals of parapsychology. Harry Price investigated Borley Rectory which is often called "the most haunted house in England." In the Rosenheim case of 1967, Dr. Friedbert Karger was one of two physicists from the Max Planck Institute who helped to investigate perhaps the most validated poltergeist case in recorded history. Annemarie Schneider, a 19-year-old secretary in a law firm in Rosenheim (a small town in southern Germany) was seemingly the unwitting cause of much chaos in the firm, including disruption of electricity and telephone lines, the rotation of a picture, swinging lamps which were captured on video (which was one of the first times any poltergeist activity has been captured on film), and strange sounds that sounded electrical in origin were recorded. Fraud was not proven despite intensive investigation by the physicists, journalists, and the police. The effects moved with the young woman when she changed jobs until they finally faded out. Friedbert Karger's whole perspective on physics changed after investigating the events. "These experiments were really a challenge to physics," Karger says today. "What we saw in the Rosenheim case could be 100 per cent shown not to be explainable by known physics". The phenomena were witnessed by Hans Bender, the police force, the CID, reporters, and the physicists. The claims were aired in a documentary in 1975 in a series called "Leap in the Dark."