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cosmic microwave background

Cultural  
  1. The microwave radiation that arrives at the Earth from every direction in space. The detection of this radiation played an important role in acceptance of the Big Bang theory.


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This radiation is sometimes referred to as the “echo” of the Big Bang.

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Upcoming galaxy surveys, cosmic microwave background studies, and gravitational wave detectors are reaching the sensitivity needed to examine ideas that were once purely theoretical.

From Science Daily Mar. 30, 2026

The cosmic microwave background, which is the faint afterglow left behind by the Big Bang, contains valuable information about the early universe.

From Science Daily Mar. 16, 2026

They’ve measured the cosmic microwave background, or leftover radiation from the Big Bang, with extremely high precision to help paint a picture of the first nanoseconds of the universe.

From Salon Jan. 17, 2025

Throughout the decades, numerous observations of how dust, gas, and ripples in the cosmic microwave background, or the leftover radiation from the primordial plasma of the universe, moved indicated that dark matter exists.

From Salon Dec. 26, 2024

“This could lead to something really groundbreaking,” Dr. Soares-Santos said, comparing it to the discovery of the cosmic microwave background in the 1960s, which has since transformed physicists’ knowledge about the early universe.

From New York Times Jun. 28, 2023

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