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Le Châtelier's principle

(Encyclopedia)Le Châtelier's principle, chemical principle that states that if a system in equilibrium is disturbed by changes in determining factors, such as temperature, pressure, and concentration of components...

Heisenberg, Werner

(Encyclopedia)Heisenberg, Werner vĕrˈnər hīˈzənbĕrk [key], 1901–76, German physicist. One of the founders of the quantum theory, he is best known for his uncertainty principle, or indeterminacy principle, ...

teleportation, in physics

(Encyclopedia)teleportation, in physics, the transfer of key properties from one particle (or group of particles) to another a significant distance apart without a physical connection between the two particles (or ...

causality

(Encyclopedia)causality, in philosophy, the relationship between cause and effect. A distinction is often made between a cause that produces something new (e.g., a moth from a caterpillar) and one that produces a c...

Knight, Frank Hyneman

(Encyclopedia)Knight, Frank Hyneman, 1885–1972, American economist, b. McLean County, Ill., Ph.D. Cornell, 1916. He taught economics at the Univ. of Chicago (1927–62). Knight's most influential work was his fir...

Simon, Herbert Alexander

(Encyclopedia)Simon, Herbert Alexander, 1916–2001, American social scientist and economist, b. Milwaukee, grad. Univ. of Chicago (B.A., 1936, Ph.D., 1943). A professor of computer science and psychology at Carneg...

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...

world soul

(Encyclopedia)world soul, Lat. anima mundi, in philosophy, term denoting a universal spirit or soul that functions as an organizing principle. While many early Greek philosophers saw the world as of one principle, ...

Allais, Maurice Félix Charles

(Encyclopedia)Allais, Maurice Félix Charles môrēsˈ shärl älĕˈ [key], 1911–2010, French economist, Ph.D. Univ. of Paris, 1949. After working in the French mine administration, he joined the École National...

measurement

(Encyclopedia)measurement, determination of the magnitude of a quantity by comparison with a standard for that quantity. Quantities frequently measured include time, length, area, volume, pressure, mass, force, and...