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quantum theory

(Encyclopedia)quantum theory, modern physical theory concerned with the emission and absorption of energy by matter and with the motion of material particles; the quantum theory and the theory of relativity togethe...

quantum field theory

(Encyclopedia)quantum field theory, study of the quantum mechanical interaction of elementary particles and fields. Quantum field theory applied to the understanding of electromagnetism is called quantum electrodyn...

quantum chromodynamics

(Encyclopedia)quantum chromodynamics (QCD), quantum field theory that describes the properties of the strong interactions between quarks and between protons and neutrons in the framework of quantum theory. Quarks p...

quantum electrodynamics

(Encyclopedia)quantum electrodynamics (QED), quantum field theory that describes the properties of electromagnetic radiation and its interaction with electrically charged matter in the framework of quantum theory. ...

electroweak theory

(Encyclopedia)electroweak theory, a unified field theory that describes two of the fundamental forces in nature, electromagnetism (see electromagnetic radiation) and the weak interaction. The electroweak theory der...

theory

(Encyclopedia)theory, in music, discipline involving the construction of cognitive systems to be used as a tool for comprehending musical compositions. The discipline is subdivided into what can be called speculati...

correspondence principle

(Encyclopedia)correspondence principle, physical principle, enunciated by Niels Bohr in 1923, according to which the predictions of the quantum theory must correspond to the predictions of the classical theories of...

domino theory

(Encyclopedia)domino theory, the notion that if one country becomes Communist, other nations in the region will probably follow, like dominoes falling in a line. The analogy, first applied (1954) to Southeast Asia ...

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