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.

Example Sentences

The other looks much farther back in time, using the cosmic microwave background to estimate what the expansion rate should be today based on the standard model of cosmology.

From Science Daily • Apr. 12, 2026

The second method, called the early relic method, involves measuring the leftover light from the Big Bang in what is called the cosmic microwave background.

From Salon • Dec. 9, 2024

For example, scientists have already compared the new quasar map with the oldest light in our cosmos, the cosmic microwave background.

From Science Daily • Mar. 18, 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

Another strong indication of the big-bang is cosmic microwave background radiation.

From Textbooks • Jan. 1, 2017