background radiation

noun

Definition of background radiation

: the microwave radiation pervading the universe that exhibits a corresponding blackbody temperature of 2.7 K and that is the principal evidence supporting the big bang theory

called also cosmic background radiation

Examples of background radiation in a Sentence

Recent Examples on the Web Many factors contribute to errors in quantum systems, including the environment, noise from internal components, background radiation, cabling, and even noise caused by qubits themselves. Paul Smith-goodson, Forbes, 15 June 2021 The needle jumps, showing a reading 50% higher than the already elevated background radiation. Gavin Blair, The Christian Science Monitor, 26 Feb. 2021 The aircraft belong to the Energy Department’s National Nuclear Security Administration, which is testing naturally occurring background radiation levels ahead of the 2021 presidential inauguration. Gabriel T. Rubin, WSJ, 23 Oct. 2020 The federal helicopter survey was originally supposed to fly above parts of the Bay Area as part of a research project to study background radiation levels. Cynthia Dizikes, SFChronicle.com, 3 Sep. 2020 That means, Martens said, that there’s about a 2 in 10,000 chance that random background radiation produced the signal as opposed to solar axions themselves. Rafi Letzter, Scientific American, 17 June 2020 But all detectors, no matter how well-shielded, experience noise from sources such as background radiation. Daniel Garisto, Scientific American, 9 June 2020 Peebles and his colleagues had predicted this background radiation, a result of when the universe, about 400,000 years after the Big Bang, cooled off enough for hydrogen and helium atoms to form. BostonGlobe.com, 9 Oct. 2019 Further such tests, and more refined observations of other cosmological features (such as the remnant microwave background radiation generated when the universe was young), might still someday find flaws in general relativity. Tom Siegfried, Scientific American, 21 Jan. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'background radiation.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of background radiation

1968, in the meaning defined above

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Time Traveler for background radiation

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The first known use of background radiation was in 1968

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Dictionary Entries Near background radiation

background projection

background radiation

backhand

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Cite this Entry

“Background radiation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/background%20radiation. Accessed 17 Sep. 2021.

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