Antigravity Hills are Visual Illusions

  title={Antigravity Hills are Visual Illusions},
  author={Paola Bressan and Luigi Garlaschelli and Monica Barracano},
  journal={Psychological Science},
  pages={441 - 449}
Antigravity hills, also known as spook hills or magnetic hills, are natural places where cars put into neutral are seen to move uphill on a slightly sloping road, apparently defying the law of gravity. We show that these effects, popularly attributed to gravitational anomalies, are in fact visual illusions. We re-created all the known types of antigravity spots in our laboratory using tabletop models; the number of visible stretches of road, their slant, and the height of the visible horizon… 

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