Definition of quantum chromodynamics

: a theory of fundamental particles based on the assumption that quarks are distinguished by differences in color (see color entry 1 sense 15) and are held together (as in hadrons) by an exchange of gluons Quantum chromodynamics equations describe the characteristics and behavior of quarks and the peculiar force that binds different quarks and antiquarks together to create protons, neutrons, and other subatomic particles known as hadrons.— I. Peterson

Examples of quantum chromodynamics in a Sentence

Recent Examples on the Web But their theory of the strong force, quantum chromodynamics, didn’t behave in the usual way, and neither did the particles. Quanta Magazine, "What Goes On in a Proton? Quark Math Still Conflicts With Experiments.," 6 May 2020 This theoretical work revitalized the nearly moribund quantum field theory and gave birth to QCD (quantum chromodynamics), the theory of the strong interactions. Peter Byrne, Quanta Magazine, "Waiting for the Revolution," 24 May 2013 One of those alternatives is the axion, a particle first proposed as a way of solving problems in an unrelated area of physics called quantum chromodynamics. John Timmer, Ars Technica, "Dark matter link to regular matter’s dominance fails to show up," 16 Nov. 2019 The strong nuclear has quantum chromodynamics, electromagnetism has quantum electrodynamics, the weak nuclear has quantum flavordynamics. Richard Panek, Twin Cities, "Richard Panek: Gravity? Who knows?," 5 Oct. 2019 But the theory of the strong force, called quantum chromodynamics (QCD), is so complicated that no one has been able to predict exactly how matter will behave at high temperatures and densities. Quanta Magazine, "Physicists Peer Inside a Fireball of Quantum Matter," 30 July 2019

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

1975, in the meaning defined above

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26 May 2020

Cite this Entry

“Quantum chromodynamics.” Dictionary, Merriam-Webster, Accessed 11 Jul. 2020.

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