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gluon

(Encyclopedia)gluon, an elementary particle that mediates, or carries, the strong, or nuclear, force. In quantum chromodynamics (QCD), the quantum field theory of strong interactions, the interaction of quarks (to ...

computer graphics

(Encyclopedia)computer graphics, the transfer of pictorial data into and out of a computer. Using analog-to-digital conversion techniques, a variety of devices—such as curve tracers, digitizers, and light pens—...

conch

(Encyclopedia)conch kŏngk, kŏnch, kôngk [key], common name for certain marine gastropod mollusks having a heavy, spiral shell, the whorls of which overlap each other. In conchs the characteristic gastropod foot ...

barometer

(Encyclopedia)CE5 Aneroid barometer barometer bərŏmˈətər [key], instrument for measuring atmospheric pressure. It was invented in 1643 by the Italian scientist Evangelista Torricelli, who used a column...

Shankar, Ravi

(Encyclopedia)Shankar, Ravi (Robindra Shankar Chowdhury), 1920–2012, Indian sitarist and composer, b. Varanasi. He was the first Indian instrumentalist to attain an international reputation and is credited with i...

Petrobras scandal

(Encyclopedia)Petrobras scandal, Brazilian corruption scandal involving executives at the government-controlled oil company, Petróleo Brasileiro S.A. (Petrobras), prominent politicians, and construction firms work...

red shift

(Encyclopedia)red shift or redshift, in astronomy, the systematic displacement of individual lines in the spectrum of a celestial object toward the red, or longer wavelength, end of the visible spectrum. The effect...

pump

(Encyclopedia)pump, device to lift, transfer, or increase the pressure of a fluid (gas or liquid) or to create a vacuum in an enclosed space by the removal of a gas (see vacuum pumps under vacuum). The centrifugal ...

virtual reality

(Encyclopedia)virtual reality (VR) or virtual environment (VE), computer-generated environment with and within which people can interact. The advantage of VR is that it can immerse people in an environment that wou...

Calder, Alexander

(Encyclopedia)Calder, Alexander kôlˈdər [key], 1898–1976, American sculptor, b. Philadelphia; son of Alexander Stirling Calder and grandson of Alexander Mine Calder, prominent sculptors. Among the most innovat...