We have no idea what causes Gravity
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This has been a fun thread to read. Your comment reminded me of something.
In 1968, my employer sent me to the university in Iowa City IA for a two week seminar on statistics. At the entrance to the student union bldg. there was a very large chalk board where students were allowed to write pithy statements.
One such comment was, “There is no such thing as gravity! The Earth sucks!”