@article{ref1,
title="Antigravity hills are visual illusions",
journal="Psychological science",
year="2003",
author="Bressan, Paola and Garlaschelli, Luigi and Barracano, Monica",
volume="14",
number="5",
pages="441-449",
abstract="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 were systematically varied in four experiments. We conclude that antigravity-hill effects follow from a misperception of the eye level relative to gravity, caused by the presence of either contextual inclines or a false horizon line.<p /> <p>Language: en</p>",
language="en",
issn="0956-7976",
doi="",
url="http://dx.doi.org/"
}