Rapid temperature changes are considered by many to be an indicator of paranormal activity.  That theory being, in the simplest terms, that the energy needed for an entity to manifest itself is drawn (in the form of heat) from it's surroundings.  Pictured here is a digital laser thermometer.  It is used to detect temperature changes in a specific area under investigation.  It is a very simple point and click type device and is extremely accurate.  In order for this equipment to be used to it's potential value, background temperature readings should be taken in investigation areas prior to beginning the investigation.

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