After death, the living will be possessed by ghosts and their voices will change. What's going on here?

According to the soul theory, the soul is a kind of energy. Law of conservation of energy, energy never dies. So this energy is looking for a carrier. Relatives, neighbors and the dead have more contact and similar breath, so it is easy to attract this energy. So for a while, I will not adapt to unexpected energy and do some incredible things. After a while, the energy dissipates and the possessed person will return to normal!