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

While dark matter keeps individual galaxies together, dark energy propels all the galaxies in the universe apart from one another. Brian Resnick, Vox, "Scientists weighed all the mass in the Milky Way galaxy. It’s mind-boggling.," 27 June 2019 Surveying them should shed light on the evolution of the universe and the nature of the dark energy that is accelerating its expansion. Daniel Clery, Science | AAAS, "Telescope designed to study mysterious dark energy keeps Russia’s space science hopes alive," 10 June 2019 Adam Riess at the Space Telescope Science Institute, who shared the 2011 Nobel Prize in physics for the discovery of dark energy, is alternately amazed and amused by the latest turn of events. Corey S. Powell, Discover Magazine, "Why We Still Don't Know How Fast the Universe is Expanding," 1 Jan. 2019 Physicists estimate some 27 percent of the total universe is dark matter and the rest (68 percent) is a similarly shadowy phenomenon called dark energy. Joe Lindsey, Popular Mechanics, "Filling the Void: What Is Dark Matter?," 28 May 2019 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

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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Last Updated

12 Jul 2019

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The first known use of dark energy was in 1998

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