Ehlers-Geren-Sachs theorem

proper noun

A theorem showing that if, in a given universe, all freely falling observers measure the cosmic background radiation to have exactly the same properties in all directions (isotropic), then that universe is an isotropic and homogeneous FLRW spacetime.

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Meanings

proper nounthe Ehlers-Geren-Sachs theorem
  1. A theorem showing that if, in a given universe, all freely falling observers measure the cosmic background radiation to have exactly the same properties in all directions (isotropic), then that universe is an isotropic and homogeneous FLRW spacetime.

Origin

Published in 1968 by Jürgen Ehlers, P. Geren, and Rainer K. Sachs.

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Cite this entry
APA

Ehlers-Geren-Sachs theorem. (n.d.). In WatkinsX Dictionary. Retrieved November 5, 2026, from https://dictionary.watkinsx.com/word/Ehlers-Geren-Sachs%20theorem

MLA

“Ehlers-Geren-Sachs theorem.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/Ehlers-Geren-Sachs%20theorem. Accessed November 5, 2026.

Chicago

WatkinsX Dictionary, s.v. “Ehlers-Geren-Sachs theorem,” accessed November 5, 2026, https://dictionary.watkinsx.com/word/Ehlers-Geren-Sachs%20theorem.

Source: Ehlers-Geren-Sachs theorem on Wiktionary, CC BY-SA 4.0.