I don't know much about cosmology or atoms, etc.., but I am under the impression that we are all made of of several different kinds of atoms. I wonder if ghosts are made up of atoms as well, and how they would be tied to the original host. I'm reaching, I know, and probably way off, but there must be some explanation for this phenomena.
When I was in indonesia recently I experienced something strange in a room I was staying in. The first night, nothing happened, except that I woke up around 3:00 am. The next night I had trouble sleeping. I kept feeling like I was being watched the whole time. I tried to close my eyes, but kept feeling something wierd. My wife was with me too. She felt the same thing. She finally fell asleep though, and I stayed awake for awhile until sleep overtook me as well. We then both woke up at 3:00 again. I couldn't get back to sleep after that. The next day again, no sleep, my wife fell a sleep, and the I was finally so tired that I had too. Note that all the lights were on. I was having weird dreams, very weird and disturbing. All of a sudden I woke up, and guess what time it was. So, at the same time, my wife woke up too. I asked her, did she turn off all of the lights. There was the bathroom light, and two others. As sat up for a moment and put my foot on the floor, all of the lights just flickered on. The next day, I asked if there was some kind of motion sensor or something, and there was not. We switched rooms. I slept just fine after that, and through the night as well. How does one explain it.