Ghosts and apparitions:
Most folk are well aware that planet Earth is a bloody huge magnet with a core of molten iron that is covered with a solid crust. That crust consists of many deposits of ores of chemical elements among which is iron oxide. Some of that iron oxide is Fe3O4 which is magnetic iron oxide, the sort we use for coating strips of plastic film to make video and audio tape. It is also used for making hard drives of course.
What if those deposits of iron oxide just happen to record live events occurring all over planet Earth ? What if, when conditions are perfect, those 'recordings' spontaneously play back producing what our minds conceive as images of the dead ? Yes, I know that magnetic iron oxide records electrical variations in the case of tape recordings but our planet is buzzing with electrical energy.
Just a thought.