big bang


Definition of big bang

: the cosmic explosion that marked the beginning of the universe according to the big bang theory In 1965 Arno A. Penzias and Robert W. Wilson of the Bell Telephone Laboratories discovered that the space of the universe is bathed with a diffuse radiation that is assumed to persist following the "big bang" expansion of the universe from an original fireball.— V. L. Ginzburg — compare big crunch, big rip

Examples of big bang in a Sentence

Recent Examples on the Web Such signals should have first emerged about 380,000 years after the big bang, when the universe cooled enough for protons and electrons that previously filled space to coalesce into atoms of hydrogen. Anil Ananthaswamy, Scientific American, "Telescopes on Far Side of the Moon Could Illuminate the Cosmic Dark Ages," 15 Jan. 2021 Jane listens to the crackle of white noise—cosmic background radiation—a faint reminder of the big bang. Seija Rankin,, "Read Charles Yu's first work of fiction since the National Book Award-winning Interior Chinatown," 5 Jan. 2021 The real-estate industry now accounts for about 7% of Chinese GDP, having climbed steadily upward from around 4% or below at the time of the big bang privatizations of the 1990s, according to the National Bureau of Statistics. Mike Bird, WSJ, "China’s Empire of Concrete," 28 Dec. 2020 Although the big bang hypothesis for the origin of the universe was well established, the originating event itself remained a mystery; in particular, there was puzzlement about the initial conditions. Paul Davies, Scientific American, "In Memoriam: John D. Barrow," 10 Oct. 2020 The efforts, collectively called ATLAS, smash together protons to mimic the circumstances of the big bang, when everything in our universe formed, including, theoretically, dark matter. Ryan Bradley, Popular Science, "Glimpse the gold mine where scientists are searching for dark matter," 27 Oct. 2020 The big bang left ripples in the dark matter, which under its own gravity began to coalesce into the denser spots. Adrian Cho, Science | AAAS, "To explain away dark matter, gravity would have to be really weird, cosmologists say," 20 Nov. 2020 The waves continued to spread until the universe cooled enough to form neutral atoms, 380,000 years after the big bang, when the CMB was born. Adrian Cho, Science | AAAS, "To explain away dark matter, gravity would have to be really weird, cosmologists say," 20 Nov. 2020 How did the big bang shape the structure of the universe? Emily V. Driscoll, Scientific American, "A Cosmic Video Miniseries to Ponder Gravity, the Universe and Everything," 12 Nov. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'big bang.' 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 big bang

1949, in the meaning defined above

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The first known use of big bang was in 1949

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Last Updated

23 Jan 2021

Cite this Entry

“Big bang.” Dictionary, Merriam-Webster, Accessed 26 Jan. 2021.

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