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breakwater

(Encyclopedia)breakwater, offshore structure to protect a harbor from wave energy or deflect currents. When it also serves as a pier, it is called a quay; when covered by a roadway it is called a mole. In the Unite...

sideband

(Encyclopedia)sideband, any frequency component of a modulated carrier wave other than the frequency of the carrier wave itself, i.e., any frequency added to the carrier as a result of modulation; sidebands carry t...

Ehrenfest, Paul

(Encyclopedia)Ehrenfest, Paul poul āˈrənfĕst [key], 1880–1933, Austrian physicist. In 1904, Ehrenfest received his doctorate in theoretical physics in Vienna and married the Russian mathematician Tatyana Alex...

virtual telescope

(Encyclopedia)virtual telescope, a computerized interferometer (see interference) that merges the images from two or more telescopes to obtain a single, large, enhanced image. The image in each telescope is made fr...

Appleton, Sir Edward Victor

(Encyclopedia)Appleton, Sir Edward Victor, 1892–1965, English physicist, grad. St. John's College, Cambridge. After returning from active service in World War I, he became assistant demonstrator in experimental p...

Yang, Chen-ning

(Encyclopedia)Yang, Chen-ning chĕn-nĭng yäng [key], 1922–, American physicist, b. China, Ph.D. Univ. of Chicago, 1948. Yang was a member of the Institute for Advanced Study at Princeton, N.J. from 1949 to 1955...

Bridgman, Percy Williams

(Encyclopedia)Bridgman, Percy Williams, 1882–1961, American physicist, b. Cambridge, Mass., grad. Harvard (B.A., 1904; Ph.D., 1908). From 1910 he taught at Harvard, as professor from 1919. He won the 1946 Nobel P...

Bohr, Aage Niels

(Encyclopedia)Bohr, Aage Niels ägə nēls bōr [key], 1922–2009, Danish physicist, Ph.D. Univ. of Copenhagen, 1954. He worked with his father Niels Bohr (who won the Nobel Prize in Physics in 1922) in the 1940s ...

Randall, Lisa

(Encyclopedia)Randall, Lisa, 1962–, American theoretical physicist and writer, b. New York City, B.A. Harvard University, 1983, Ph.D. Harvard University, 1987. Rand...

neutron

(Encyclopedia)neutron, uncharged elementary particle of slightly greater mass than the proton. It was discovered by James Chadwick in 1932. The stable isotopes of all elements except hydrogen and helium contain a n...