dark energy


Definition of dark energy

: a hypothetical form of energy that produces a force that opposes gravity and is thought to be the cause of the accelerating expansion of the universe

Examples of dark energy in a Sentence

Recent Examples on the Web

More recently, the spirit of aether has even come back into the discussion of the cosmos, thanks to the mysterious discoveries of dark matter and dark energy, the elusive force believed to be the cause of the accelerating expansion of the universe. Meg Neal, Popular Mechanics, "The Eternal Quest for Aether, the Cosmic Stuff That Never Was," 19 Oct. 2018 Will dark matter and dark energy ever be actually seen? Samantha Mathewson, Space.com, "Mysterious Milky Way Signal Comes from the Past, Not Dark Matter," 13 Mar. 2018 The identity of dark matter and dark energy involve fundamental questions about how the Universe is constructed. John Timmer, Ars Technica, "We’ve seen more fast radio bursts, but we still don’t know what they are," 11 Oct. 2018 And dark matter and dark energy are key features of the standard model. Mike Wall, Space.com, "Observations of the Early Universe Reaffirm the Existence of Dark Matter and Dark Energy," 18 July 2018 Theorists have dozens of alternative gravity theories that could potentially explain dark matter and dark energy, Freire said. Katia Moskvitch, WIRED, "Troubled Times for Alternatives to Einstein’s Theory of Gravity," 6 May 2018 Similarly, in 1998 cosmologists found evidence the universe is expanding faster than expected, driven by an even more mysterious dark energy. Maya Miller, Scientific American, "Einstein’s Greatest Theory Validated on a Galactic Scale," 22 June 2018 But these Nobel-busting reasons apply equally to dark energy’s discoverers, too. Brian Keating, WIRED, "There's Nothing Noble about Science’s Nobel Prize Gender Gap," 27 May 2018 Astronomers have also studied the cosmic microwave background — the oldest light in the universe, which permeates the entire sky — and found roughly the same proportions of normal matter, dark matter and dark energy. Amina Khan, latimes.com, "After years of searching, scientists can finally account for all the normal matter in the universe," 20 June 2018

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

1998, in the meaning defined above

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The first known use of dark energy was in 1998

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to affect and impair by alcohol or a drug

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