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quantum theory

noun, Physics.
1.
any theory predating quantum mechanics that encompassed Planck's radiation formula and a scheme for obtaining discrete energy states for atoms, as Bohr theory.
2.
any theory that treats certain phenomena by the methods of quantum mechanics:
a quantum theory of gravitation.
Origin
1910-1915
1910-15
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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British Dictionary definitions for quantum-theory

quantum theory

noun
1.
a theory concerning the behaviour of physical systems based on Planck's idea that they can only possess certain properties, such as energy and angular momentum, in discrete amounts (quanta). The theory later developed in several equivalent mathematical forms based on De Broglie's theory and on the Heisenberg uncertainty principle See wave mechanics
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
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quantum-theory in Medicine

quantum theory n.
The theory that radiant energy is transmitted in the form of discrete units.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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quantum-theory in Science
quantum theory  
  1. See quantum mechanics.

  2. Any of various theories that makes use of the assumptions, principles, and laws of quantum mechanics.


The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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