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Summary
DescriptionGravitional well.jpg
English: An illustration of the cosmological redshift. To an observer positioned at the centre of a gravitational well, the periphery of the well appears to be increasingly redshifted.
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{{Information |Description={{en|1=An illustration of the cosmological redshift. To an observer positioned at the centre of a gravitational well, the periphery of the well appears to be redshifted.}} |Source=http://en.wikipedia.org/wiki/File:GravityPotenti