Columbia Encyclopedia

Search results

500 results found

teleportation, in physics

(Encyclopedia)teleportation, in physics, the transfer of key properties from one particle (or group of particles) to another a significant distance apart without a physical connection between the two particles (or ...

optical disk

(Encyclopedia)optical disk, any of a variety of information storage disks that are played or read using a laser. Optical disks include compact discs (CDs and CD-ROMs), laser discs (see videodisc), and digital versa...

Fred Lawrence Whipple Observatory

(Encyclopedia)Fred Lawrence Whipple Observatory, astronomical observatory located 35 mi (56 km) S of Tucson, Ariz., at an altitude of 8,500 ft (2,590 m). It is operated jointly by the Smithsonian Astrophysical Obse...

stun gun

(Encyclopedia)stun gun, hand-held electronic device that produces a high-voltage pulse that can immobilize a person for several minutes with no permanent damage in most cases. It is powered by ordinary batteries, w...

Callahan, Harry Morey

(Encyclopedia)Callahan, Harry Morey, 1912–99, American photographer, b. Detroit. Self-taught, he began taking pictures (1938) as a hobby and, inspired by the work of Ansel Adams, began to produce professional-qua...

cesarean section

(Encyclopedia)cesarean section sĭzârˈēən [key], delivery of an infant by surgical removal from the uterus through an abdominal incision. The operation is of ancient origin: indeed, the name derives from the le...

Angkor

(Encyclopedia)Angkor ăngˈkôr [key], site of several capitals of the Khmer Empire, north of Tônlé Sap, NW Cambodia, for about five and a half centuries (9th to 15th), the heart of the empire. Extending over an ...

Némcová, Božena

(Encyclopedia)Némcová, Božena bôˈzhĕnä nĕmˈtsôvä [key], 1820–62, Czech novelist and storyteller. Némcová developed the regional tale, which she enhanced with an original prose style. Her work provide...

Alcman

(Encyclopedia)Alcman ălkˈmən [key], fl. 620 b.c., Greek lyric poet of Sparta. He was the earliest writer of Dorian choral poetry whose work has survived. Short choral fragments and a longer one (part of a parthe...

Chalkley, Thomas

(Encyclopedia)Chalkley, Thomas chôˈklē [key], 1675–1741, Quaker mariner and missionary preacher, b. England. He made his home after 1701 in Philadelphia. He traded chiefly with the West Indies, navigating his ...