What are some scientific explanations as to what "ghosts" actually are or could be?

by Bibliothèque de Toulouse

Question by : What are some scientific explanations as to what "ghosts" actually are or could be?
I'm not looking for proof or evidence. I'm looking for theories. Also if the theory isn't your own, please site where the theory originated from. I tend to be skeptical on this subject but I'm not completely opposed to reasonable explanations as to what these supposed forces may be.


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