relativity

noun
rel·​a·​tiv·​i·​ty | \ ˌre-lə-ˈti-və-tē How to pronounce relativity (audio) \
plural relativities

Definition of relativity

1a : the quality or state of being relative
b : something that is relative
2 : the state of being dependent for existence on or determined in nature, value, or quality by relation to something else
3a : a theory which is based on the two postulates (1) that the speed of light in a vacuum is constant and independent of the source or observer and (2) that the mathematical forms of the laws of physics are invariant in all inertial systems and which leads to the assertion of the equivalence of mass and energy and of change in mass, dimension, and time with increased velocity

called also special relativity, special theory of relativity

b : an extension of the theory to include gravitation and related acceleration phenomena

called also general relativity, general theory of relativity

Examples of relativity in a Sentence

Recent Examples on the Web But there's no shortage of strangeness in another one of physics' cornerstone theories: relativity. John Timmer, Ars Technica, "White dwarf causes strange relativity effect called frame dragging," 1 Feb. 2020 The result would be no mere picture but a trove of pixels against which to test our ideas about gravity, relativity and the behavior of matter in extremis. Alan Hirshfeld, WSJ, "Book Review: Feeling Gravity’s Pull," 16 Nov. 2018 Already, the instrument has confirmed Einstein’s theory of relativity and recorded the collision of two black holes. Popsci Staff, Popular Science, "The best tech of the last decade," 27 Dec. 2019 In a pivotal twist, the hero Cooper (Matthew McConaughey) is punished by the power of relativity. David Sims, The Atlantic, "The 10 Best Movie Scenes of the 2010s," 31 Dec. 2019 Whereas relativity says the same laws apply for observers on moving platforms, spatial translation symmetry says the same laws apply for observers on platforms in different places. Frank Wilczek, Scientific American, "The Exquisite Precision of Time Crystals," 16 Oct. 2019 Before Albert Einstein propounded his theory of relativity in the early 20th century, it was assumed that matter could ultimately be broken down into indivisible indestructible parts. Harish Pullanoor, Quartz India, "How the Indian icon Nataraja danced his way from ancient history to modern physics," 18 Dec. 2019 Though Einstein later doubted their existence, these spacetime wrinkles—called gravitational waves—are a key prediction of relativity, and the search for them captivated researchers for decades. Michael Greshko, National Geographic, "These are the top 20 scientific discoveries of the decade," 5 Dec. 2019 The next step in our understanding of crystals is occurring now, thanks to a principle that arose from Albert Einstein's relativity theory: space and time are intimately connected and ultimately on the same footing. Frank Wilczek, Scientific American, "The Exquisite Precision of Time Crystals," 16 Oct. 2019

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

circa 1834, in the meaning defined at sense 1a

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Time Traveler for relativity

Time Traveler

The first known use of relativity was circa 1834

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Statistics for relativity

Last Updated

20 Feb 2020

Cite this Entry

“Relativity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/relativity. Accessed 22 Feb. 2020.

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More Definitions for relativity

relativity

noun
How to pronounce relativity (audio)

English Language Learners Definition of relativity

physics : a theory developed by Albert Einstein which says that the way that anything except light moves through time and space depends on the position and movement of someone who is watching

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