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baryon

(Encyclopedia)baryon bârˈēŏnˌ [key] [Gr.,=heavy], class of elementary particles that includes the proton, the neutron, and a large number of unstable, heavier particles, known as hyperons. From a technical poi...

Rosenberg Case

(Encyclopedia)Rosenberg Case, in U.S. history, a lengthy and controversial espionage case. In 1950, the Federal Bureau of Investigation arrested Julius Rosenberg (1918–53), an electrical engineer who had worked (...

Gorbachev, Mikhail Sergeyevich

(Encyclopedia)Gorbachev, Mikhail Sergeyevich mēkhəyēlˈ sĭrgāˈyəvich gərbəchofˈ ...

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...

Marshall Islands

(Encyclopedia)Marshall Islands, officially Republic of the Marshall Islands, independent nation (2015 est. pop. 53,000), in the central Pacific. The Marshalls extend over a 700-mi (1,130-km) area and comprise two m...

entropy

(Encyclopedia)entropy ĕnˈtrəpē [key], quantity specifying the amount of disorder or randomness in a system bearing energy or information. Originally defined in thermodynamics in terms of heat and temperature, e...

hot spring

(Encyclopedia)hot spring, natural discharge of groundwater having an elevated temperature. Most hot springs result from the emergence of groundwater that has passed through or near recently formed, hot, igneous roc...

phosphorescence

(Encyclopedia)phosphorescence fŏsˌfərĕsˈəns [key], luminescence produced by certain substances after absorbing radiant energy or other types of energy. Phosphorescence is distinguished from fluorescence in th...

Douglas-Home, Alexander Frederick, Baron Home of the Hirsel

(Encyclopedia)Douglas-Home, Alexander Frederick, Baron Home of the Hirsel dŭgˈləs-hyo͞om [key], 1903–95, British politician. Educated at Eton and Oxford, he was elected to the House of Commons in 1931 as a Co...

Athens, cities, United States

(Encyclopedia)Athens. 1 City (2020 population 25406), seat of Limestone co., N Al; inc. 1818. One of the first incorporated cities in Alabma, the city was established a year before the state was ...