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An acquaintance of mine, while being home alone, saw that the light bulb in the room which was hanging from the ceiling with wires having a pendulum motion which was more than noticeable. He says that that was a ghost but i know better than that.

I just can't find an explanation. Maybe you can help.

The light bulb was ON at the time. Some windows in the flat could have been open but the person said he was in the room at that time and there was no draft.

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closed as too localized by Ron Maimon, David Z Oct 7 '11 at 20:28

This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center.If this question can be reworded to fit the rules in the help center, please edit the question.

It is a mechanical resonance. This question should be closed. – Ron Maimon Oct 7 '11 at 19:48
Long pendulums with small amplitude can be in noticeable motion for a long time -- speed and cross section is small and so is friction. IMO this is may be a reason of the behavior you observed; make an experiment -- poke this bulb on your own and check how long will it swing. – mbq Oct 8 '11 at 8:13

Maybe there was a tiny draft and the person didn't notice. It's not impossible.

Maybe there was a small earthquake, small enough to not be perceived, but big enough to impart a tiny but visible swinging motion to various objects like that. I live in California, and whenever I feel there might have been a tiny earthquake, I look at objects hanging like that - if they are swinging, chances are there was an EQ; if they aren't, chances are there wasn't.

Maybe a large truck passed on the street and caused vibrations.

Maybe someone next door were dancing or jumping and caused vibrations through the building.

There are so many possibilities.

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