Poltergeist is the term used in Parapsychology to describe uncontrolled Psychokinesis or RSPK.(The ability to move objects with the mind or cause some disturbances) The word Poltergeist is a German word that means 'noisy ghost'. Many ghost hunters use the word to describe any noise believed to be created by a spirit or other entity.

True poltergiests in Parapsychology terms are believed to be created by an agent, which is most often a young female between the ages of twelve and twenty four. Often electrical disturbances are reported during an active manifestation of a Poltergeist. The activity normally occurs when the agent is under some stress. The stress may come from the subconscious and be unknown to the agent that they are the cause of the activity.The reported activity can be anything from simple noises to objects moving with no seen reason. Poltergeists seem to grow in intensity as the phenomenon continues. The activity may start as sounds and grow to the point where large objects and furniture move about. Voices may also be heard during the activity. Sometimes it is reported people see what appears to be apparitions during these cases. Some cases in the past reported fires just started around the location. "Pyrokinesis" 

Parapsychologists will continue to study the Poltergeist phenomenon until more is known about the subject. One interesting case is the Enfield Ghost / Poltergiest.  The only way to learn is by questioning what you "think or believe " to truly find the answers! One has to research outside the parameters of your perceived reality.  This is what PROS continues to research and investigate. 

Sometimes, there may be a known or believed cause for these type events. Most may have more than one possible answer if we seek further than what we believe is the answer. PROS will seek answers looking at many records and documented events in history. Subjects like "Geometry" may be one answer with the recorded events like " Tri-angles" or "Ley Lines." One has to research to find answers. Many strange happenings are said and documented history with in these Tri-angles. From orbs, Cryptids, and other recorded phenomenon. In some cases. This may be areas where these things happen!  Twelve Devil's Triangles around the World   Another factor could be the "Multi Verse." link-  Multiverse - Wikipedia