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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...

axiom

(Encyclopedia)axiom, in mathematics and logic, general statement accepted without proof as the basis for logically deducing other statements (theorems). Examples of axioms used widely in mathematics are those relat...

Babel, Isaac Emmanuelovich

(Encyclopedia)Babel, Isaac Emmanuelovich ēˈsäk əmäno͞oāˈləvĭch bäˈbəl [key], 1894–1940, Russian writer, b. Odessa. Babel was quick to embrace the Bolshevik revolution of 1917, but in the end it was t...

Gates, Robert Michael

(Encyclopedia)Gates, Robert Michael, 1943–, American government official, U.S. secretary of defense (2006–11), b. Wichita, Kans. A circumspect and pragmatic career intelligence officer, he joined (1966) the Cen...

humor

(Encyclopedia)humor, according to ancient theory, any of four bodily fluids that determined human health and temperament. Hippocrates postulated that an imbalance among the humors (blood, phlegm, yellow bile, and b...

jerboa

(Encyclopedia)jerboa jərbōˈə [key], name for the small, jumping rodents of the family Dipodidae, found in arid parts of Asia, N Africa, and SE Europe. Jerboas have extremely long hind feet and short forelegs; t...

electrodynamics

(Encyclopedia)electrodynamics, study of phenomena associated with charged bodies in motion and varying electric and magnetic fields (see charge; electricity); since a moving charge produces a magnetic field, electr...

Johnson, Boris

(Encyclopedia)Johnson, Boris (Alexander Boris de Pfeffel Johnson), 1964–, British political leader, b. New York City, grad. Oxford (1986). While at Oxford Johnson was president of the prestigious Oxford Union deb...

Struve

(Encyclopedia)Struve shtro͞oˈvə [key], family of astronomers. Friedrich Georg Wilhelm von Struve, 1793–1864, was born in Germany but later lived in Russia. While director (1817–39) of Dorpat Observatory he w...