The Law of Conservation of Energy states that energy cannot be created or destroyed, only changed from one form to another. If the human spirit is energy, then upon death the energy of that essence needs to go somewhere.

Three teams of paranormal investigators descended on Lehi's Hutchings Museum in May 2008, spending the night searching for ghouls.
The teams fanned out, poking into the museum's nooks and crannies with thousands of dollars of high-tech equipment, hoping to catch the voice of a ghost on tape or an image on film, or even just the electromagnetic signature of the disembodied.
“Not only is the [Hutchings] Museum haunted, the ghosts can be rather, er, physical,” said Michelle Lowe of, one of the teams that spent the night investigating. "It was interesting," she said. "We didn't expect much to happen, but we had a couple of experiences."
Investigators several times heard what sounded to be "additional footsteps, like people were being followed through the basement," she said.
One of the investigators was grabbed on the leg by a ghost, she said.

John Hutchings Museum, Located in Lehi’s Veterans Memorial Building. 55 N. Center St 801-768-7180 Tues-Sat 11:00am to 5:00pm

 "There is no 911 for ghosts and hauntings, and some people need help and don't know what to do," said Amber Mandic of "Some people even sell their homes to get away from it."
Paranormal investigators can discover the cause and give advice for getting a haunt to leave, she said. And sometimes, what looks to be a paranormal problem is actually something much simpler.
On one occasion, what a homeowner was convinced was a ghost turned out to be a raccoon in the attic, said Mandic. One another occasion, the culprit of strange noises was a bat
Sometimes, when investigators find ghosts, the homeowners are pleased, having just wanted confirmation all along that they "are not crazy," investigators said.

And sometimes, homeowners want the ghosts to hit the road, the solution to which could be as simple as redecorating -- painting a haunted room pink and putting up Disney-themed decor can get rid of a surly male ghost, for instance.