"Poltergeist" is a German word meaning "noisy spirit." en.wikipedia.org...
Now these are interesting, previously we thought that they were more "wicked" and active ghosts, however more and more it appears that activity seems to centre around an individual,
The mind (not brain or ego) is responsible for creating the reality we exist in. And activity associated with Poltergeists is I Believe psychokinetic activity as a result of emotional, psychological or physical stress. Abuse victims and teens, people going though a trauma will be the ones associated with the activity. This could also mean that a ghost form is given more "power" by the energy that is created from the trauma/distress.
Poltergeists can be quite violent, and have a power to move objects and create visual terror such as blood on walls, or on a person.
Famous Poltergeist examples
Like many paranormal phenomena, poltergeist stories date back well into history. Poltergeist activity was reported as early as 530 C.E., in the home of the chief physician to the Ostrogoth King Theodoric. In 858 C.E., a report of supernatural stone throwing comes from the small town of Bingen on the Rhine, where Romans were fighting the Gauls.*
The Rosenheim Poltergeist in 1967, where a Bavarian attorney's office was plagued by electrical phenomena such as the unscrewing and bursting of light bulbs, the tripping of switches, and phone numbers called thousands of times, was investigated not only by psychical researchers, but also psychologists and physicists, as well as the electric company. It was found that the phenomena always occurred in the presence of a 19 year old female employee.
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The Miami Poltergeist case, also from 1967, centered around a disgruntled and recently suicidal employee in a warehouse, around whom items would fly off the shelves and break. Researchers recorded 224 separate incidents, and numerous tests were carried out to rule out fraud. The paranormal phenomena were witnessed not only by parapsychologists, but also by police officers and a professional magician.
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Depending on the power of a poltergeist, its activity can range from cold drafts, odd sounds, and foul smells to levitating objects, unseen hands, and physical abuse. Accounts of early poltergeist activity can be found in the work of ancient Roman writer Titus Livius, "Ab Urbe Condita," wherein a shower of stones scared the Roman army. Other notable records of poltergeist activity involving people being dragged away from their beds by unseen forces and of unexplainable fires were written by Jacob Grimm in his work "Deustche Mythologie." Given the largely superstitious atmosphere of that time, poltergeist activity was readily attributed to demonic powers.
But the progress of paranormal science and parapsychology during the 20th century gave rise to a new concept about the nature of poltergeists. Separate studies done by parapsychologists Nandor Fodor, Alan Gauld and A. D. Cornell, and William Roll traced poltergeist existence and activity not in paranormal entities but in humans. According to their theories on the human-poltergeist connection, the force usually ascribed to poltergeists are powerful emotional and mental triggers in the human psyche. These theories have their foundations on the idea that poltergeist.
But the progress of paranormal science and parapsychology during the 20th century gave rise to a new concept about the nature of poltergeists. Separate studies done by parapsychologists Nandor Fodor, Alan Gauld and A. D. Cornell, and William Roll traced poltergeist existence and activity not in paranormal entities but in humans. According to their theories on the human-poltergeist connection, the force usually ascribed to poltergeists are powerful emotional and mental triggers in the human psyche. These theories have their foundations on the idea that poltergeist activity usually occurs in places which have seen much violence and suffering or around persons who are experiencing deep emotional turmoils. Roll even went as far as to name the phenomenon as "recurrent spontaneous psychokinesis" or RSPK. This refers to the expression of intense emotion like hostility, anger, and sexual tension from a human agent which causes inexplicable physical manifestations such as levitation. The agent is usually oblivious to the fact the he or she caused the disturbance because it is the subconscious mind which found a way to release any repressed emotion through psychokinesis.
On the other hand, poltergeist activity without the presence of an agent is attributed to the remnants of intense emotions in a particular locale, a phenomenon similar to how a place gives one "the creeps" without any apparent reason. In this case, poltergeist activity is simply an outward manifestation of human emotion. It is perfectly controllable as long as the agent expresses pent-up feelings, hence, lessening chances of subconscious "poltergeist" activity. www.trueghosttales.com...
www.newworldencyclopedia.org...
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The Einfeld Poltergeist ia a world famous case, and the children have admitted to some fakery, it is acceptable that the girls started to imitate what was around them. There were many occurances that could not be explained by police officers, researches, press and neighbours etc. I personally think the mother was traumatised by the husband leaving, and the elder daughter for the same reason, they gave it power via their distress. Then as their fear and a media/investigation circus in the house grew, so did the poltergeists power. As the fear died down, so did the activity. The lead investigator Maurice Grosse I think liked it all a bit too much....
EVIL ENTITIES
I will only touch on as I don't think the traditional concept of Demon exists unless given power by us. Whilst evil can incarnate, it will have the ability to learn and change through life, there is also non corporeal "evil" charged energy that exists. Some say they exist outside of human experience, others say they are remnants of wicked intent that forgets the humanity it once was.
The SOUL
The soul is the immaterial part of a person; separate to yet also part of the collective mind...confusing?
A soul is identity, awareness achieved and stored as energy. It is housed in the body, and also connected to the mind. Attached to the body it is limited to one fixed time and space, and its symmetric attachment to mind is not bound by time and space.
Hate to link this site, but a good explanation
"Its the consciousness that's beyond time and space and all pervading.Mind is just a tool through which our we think and gain knowledge like how we use eyes,nose,ears to see,hear and breathe.It has neither a creation nor an end, it has no boundaries either"
www.crystalinks.com...
[edit on 26-10-2009 by zazzafrazz]
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I have experienced this with my other friends at the same time. There is much to explain. 
