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

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

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

However, I and several other people showed that, at least in its original form, it predicted much greater variations in the temperature of the microwave background radiation than are observed.

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