quantum theory

[ kwon-tuhm thee-uh-ree, theer-ee ]

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.

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

quantum theory

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

Word History and Origins

Origin of quantum theory¹

First recorded in 1910–15

Example Sentences

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

The infamous and problematic "measurement postulate" of quantum theory is not needed, since quantum superpositions necessarily localise through their interaction with classical spacetime.

From Science Daily

By connecting their new theory to quantum metrology, which uses quantum theory to make highly sensitive measurements, the Cambridge team has shown that entanglement can solve problems that otherwise seem impossible.

From Science Daily

He had cracked the code of atomic structures, determining how atoms are modeled — electrons orbiting a nucleus of protons and neutrons — and helping create quantum theory in the process.

From Salon