Columbia Encyclopedia

Search results

500 results found

dark energy

(Encyclopedia)dark energy, repulsive force that opposes the self-attraction of matter (see gravitation) and causes the expansion of the universe to accelerate. The search for dark energy was triggered by the discov...

free energy

(Encyclopedia)free energy or Gibbs free energy, quantity derived from the relationships between heat and work studied in thermodynamics and used as a measure of the relative stability of a physical or chemical syst...

geothermal energy

(Encyclopedia)geothermal energy: see energy, sources of. ...

kinetic energy

(Encyclopedia)kinetic energy: see energy.

activation energy

(Encyclopedia)CE5 Energy profile of an exothermic reaction: Although the total energy of the products is less than that of the reactants, the activation energy must be added to weaken or break existing bonds bef...

thermonuclear energy

(Encyclopedia)thermonuclear energy: see nuclear energy. ...

solar energy

(Encyclopedia)solar energy, any form of energy radiated by the sun, including light, radio waves, and X rays, although the term usually refers to the visible light of the sun. Solar energy is needed by green plants...

ElBaradei, Mohamed

(Encyclopedia)ElBaradei, Mohamed ĕlbäräˈdā [key], 1942–, Egyptian lawyer and United Nations diplomat, b. Cairo, grad. Univ. of Cairo (1962), New York Univ. School of Law (1974). He worked (1964–80) in the ...

Multilateral Investment Guarantee Agency

(Encyclopedia)Multilateral Investment Guarantee Agency (MIGA), specialized agency of the United Nations. Formed in 1988, with headquarters in Washington, D.C., it is a member of the World Bank Group (see Internatio...

Bethe, Hans Albrecht

(Encyclopedia)Bethe, Hans Albrecht bāˈtə [key], 1906–2005, American physicist, b. Strassburg, Germany (now Strasbourg, France), educated at Frankfurt and Munich universities. Fleeing Nazi Germany in 1933, he c...