quantum theory

American  

[kwon-tuhm thee-uh-ree, theer-ee] / ˈkwɒn təm ˌθi ə ri, ˌθɪər i /

noun

Physics.

1. any theory predating quantum mechanics that encompassed Planck's radiation law and a scheme for obtaining discrete energy states for atoms, such as the Bohr model.

2. any theory that treats certain phenomena by the methods of quantum mechanics.

   a quantum theory of gravitation.

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quantum theory British  

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

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quantum theory Scientific  

1. See quantum mechanics

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

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Etymology

Origin of quantum theory

First recorded in 1910–15

Example Sentences

Over time, Lorentz invariance became a foundational assumption in modern physics, especially within quantum theory.

From Science Daily

JJ: There’s so much contradiction within the music on “Quantum Baby” that mimics quantum theory.

From Los Angeles Times

The Born rule bridges the math of quantum theory to the outcomes of experiments, which makes the field a legitimate scientific discipline in the first place.

From Salon

“We want to bring it out of quantum theory and labs and take it to actual photons from stars,” Lau says.

From Science Magazine

This results in random and violent fluctuations in spacetime that are larger than envisaged under quantum theory, rendering the apparent weight of objects unpredictable if measured precisely enough.

From Science Daily