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

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 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

However, interest in evolving dark energy was vigorously rekindled last year from the combination of supernovae, baryon acoustic oscillation, and cosmic microwave background data from the DES, DESI, and Planck experiments.

From Science Daily • Nov. 4, 2025

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