Any of a number of theories in particle physics that treat elementary particles (see subatomic particle) as infinitesimal one-dimensional “stringlike” objects rather than dimensionless points in space-time. Different vibrations of the strings correspond to different particles. Introduced in the early 1970s in attempts to describe the strong force, string theories became popular in the 1980s when it was shown that they might provide a fully self-consistent quantum field theory that could describe gravitation as well as the weak, strong, and electromagnetic forces. The development of a unified quantum field theory is a major goal in theoretical particle physics, but inclusion of gravity usually leads to difficult problems with infinite quantities in the calculations. The most self-consistent string theories propose 11 dimensions; 4 correspond to the 3 ordinary spatial dimensions and time, while the rest are curled up and not perceptible.
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Ensemble consisting of two violins, viola, and cello, or a work written for such an ensemble. Since circa 1775 such works have been perhaps the predominant genre of chamber music. It was principally developed (if not quite invented) by Joseph Haydn, who wrote some 70 quartets between 1757 and 1803. Wolfgang Amadeus Mozart, Ludwig van Beethoven, Franz Schubert, Béla Bartók, and Dmitry Shostakovich are the preeminent subsequent quartet composers. Works called string quartets have traditionally observed the four-movement design of the sonata and symphony. Like most chamber music genres, quartet music was traditionally intended primarily for the private enjoyment of amateur musicians rather than for public performance.
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Any musical instrument that produces sound by the vibrations of strings. The strings may be of gut, metal, fibre, or plastic, and may be plucked, bowed, or struck. The orchestral stringed instruments include the violin, viola, cello, double bass, and harp. Keyboard stringed instruments include the clavichord, harpsichord, piano, and virginal. Seealso Aeolian harp; balalaika; dulcimer; guitar; kithara; koto; lute; lyre; mandolin; pipa; sitar;
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Double bass, viol-shaped, side and front views.
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Examples of string use include:
String may also refer to:
In science, computers or mathematics: