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Dirac, Paul Adrien Maurice

(Encyclopedia)Dirac, Paul Adrien Maurice dĭrăkˈ [key], 1902–84, English physicist. He was educated at the Univ. of Bristol and St. John's College, Cambridge, and became professor of mathematics at Cambridge in...

auteur

(Encyclopedia)auteur ōtörˈ [key], in film criticism, a director who so dominates the film-making process that it is appropriate to call the director the auteur, or author, of the motion picture. The auteur theor...

shock absorber

(Encyclopedia)shock absorber, device for reducing the effect of a sudden shock by the dissipation of the shock's energy. On an automobile, springs and shock absorbers are mounted between the wheels and the frame. W...

special effects

(Encyclopedia)special effects, in motion pictures, cinematographic techniques that create illusions in the audience's minds as well as the illusions created using these techniques. Some common examples are the use ...

vibration

(Encyclopedia)vibration, in physics, commonly an oscillatory motion—a movement first in one direction and then back again in the opposite direction. It is exhibited, for example, by a swinging pendulum, by the pr...

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...

nutation

(Encyclopedia)nutation, in astronomy, a slight wobbling motion of the earth's axis. The causes of nutation are similar to those of the precession of the equinoxes, involving the varying attraction of the moon on th...

force

(Encyclopedia)force, commonly, a “push” or “pull,” more properly defined in physics as a quantity that changes the motion, size, or shape of a body. Force is a vector quantity, having both magnitude and dir...

Empedocles

(Encyclopedia)Empedocles ĕmpĕdˈəklēz [key], c.495–c.435 b.c., Greek philosopher, b. Acragas (present Agrigento), Sicily. Leader of the democratic faction in his native city, he was offered the crown, which h...

Owl and the Nightingale, The

(Encyclopedia)Owl and the Nightingale, The, Middle English poem written probably by Nicholas de Guildford of Dorsetshire about the beginning of the 13th cent. Written in 2,000 lines of octosyllabic couplets, it des...