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

"Observations of galaxies and the cosmic microwave background suggest that some kind of dark matter exists," says Baker.

From Science Daily • Apr. 8, 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

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

In recent years, the foundation has funded a new observatory in Chile’s Atacama Desert to observe microwave background radiation from the big bang, and created the Flatiron Institute, which applies computational methods to scientific research.

From Science Magazine • May 15, 2024

Observations of the microwave background and of the abundances of the light elements indicate that the early universe did not have the kind of curvature required to allow time travel.

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