Columbia Encyclopedia

(Encyclopedia) plasma, in physics, fully ionized gas of low density, containing approximately equal numbers of positive and negative ions (see electron and ion). It is electrically conductive and is affected by magn...

(Encyclopedia) zero, that number which, when added to any number, leaves the latter unchanged; its symbol is 0. The introduction of zero into the decimal system was the most significant achievement in the developmen...

(Encyclopedia) gas laws, physical laws describing the behavior of a gas under various conditions of pressure, volume, and temperature. Experimental results indicate that all real gases behave in approximately the sa...

(Encyclopedia) heat, nonmechanical energy in transit, associated with differences in temperature between a system and its surroundings or between parts of the same system. The study of heat and its relationship ...

(Encyclopedia) nucleosynthesis or nucleogenesis, in astronomy, production of all the chemical elements from the simplest element, hydrogen, by thermonuclear reactions within stars, supernovas, and in the big bang at...

(Encyclopedia) Danish literature, the literature of Denmark. By 1900 a lyrical reaction was being led by the poet J. J. Jørgensen; impressionistic themes became important, but were never the sole fruit of Danish ...

(Encyclopedia)  CE5 Structure of the sun sun, intensely hot, self-luminous body of gases at the center of the solar system. Its gravitational attraction maintains the planets, comets, and other bodies of the sola...

(Encyclopedia) Elements 1 Parentheses indicate most stable isotope; brackets enclose lower and upper bounds of weight variation. ...

(Encyclopedia)  CE5 Denmark dĕnˈmärk [key], Dan. Danmark, officially Kingdom of Denmark, kingdom (2015 est. pop. 5,689,000), 16,629 sq mi (43,069 sq km), N Europe. It borders on Germany in the south, the North ...

(Encyclopedia)  CE5 Poland, Pol. Polska, officially Republic of Poland, republic (2015 est. pop. 38,265,000), 120,725 sq mi (312,677 sq km), central Europe. It borders on Germany in the west, on the Baltic Sea and...