[ ahy-suh-spin ]
/ ˈaɪ səˌspɪn /
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noun Physics.



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Origin of isospin

By shortening
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for isospin

/ (ˈaɪsəʊˌspɪn) /


an internal quantum number used in the classification of elementary particles. Particles which have very similar properties except for those associated with their charge are regarded as forms of the same fundamental particle with different components of the isospin in a certain direction in an imaginary spaceAlso called: isobaric spin, isotopic spin
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for isospin

[ īsə-spĭn′ ]

A vector quantity of quantum systems (especially subatomic particles) that is conserved in strong interactions and is used to characterize particles that are affected equally by the strong force but have other dissimilar properties, such as different electric charges. For example, protons and neutrons, which are indistinguishable with respect to strong force interactions, have the same isospin. Also called isotopic spin See also baryon number strangeness.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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