microwave background

British  

noun

1. a background of microwave electromagnetic radiation with a black-body spectrum discovered in 1965, understood to be the thermal remnant of the big bang with which the universe began

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microwave background Scientific  

1. See cosmic background radiation

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Example Sentences

The second method looks at the early universe by studying the cosmic microwave background, the faint radiation left over from the Big Bang.

From Science Daily • Apr. 29, 2026

Arno Penzias at Bell Labs won the Nobel Prize in Physics for discovering “cosmic microwave background radiation” from the Big Bang.

From The Wall Street Journal • Mar. 29, 2026

The team also discovered that when this phase uncertainty is considered, cosmic birefringence influences another signal in the cosmic microwave background known as the EE correlation.

From Science Daily • Mar. 16, 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

This is consistent with the observations of the microwave background radiation, which show that it has almost exactly the same intensity in any direction.

From "A Brief History of Time: And Other Essays" by Stephen Hawking