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The oldest cosmic light

The cosmic microwave background is a faint glow of light left over from the Big Bang. It fills the entire sky and records the Universe's early history. Two independent experts outline what we know about this ancient light, both theoretically and observationally.

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Figure 1: Searching for the origins of the Universe.

Steffen Richter, Harvard Univ. Brian Keating


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Correspondence to David Spergel or Brian Keating.

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Spergel, D., Keating, B. The oldest cosmic light. Nature 518, 170–171 (2015).

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