This video is a footnote for the video about the ring around the earth: https://www.youtube.com/watch?v=4xSPl...
Essentially, a ring around the earth is in unstable equilibrium, so it would stay put, but then fall one way or the other as soon as any asymmetry (even thermal or quantum fluctuations) developed.
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Footnote †: Unstable Equilibrium ─ minutephysics
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