Big

Dipper, Big, and Little Dipper: see Ursa Major and Ursa Minor.

Model of the origin of the universe, which holds that it emerged from a state of extremely high temperature and density in an explosive expansion 10 billion–15 billion years ago. Its two basic assumptions—that Albert Einstein's general theory of relativity correctly describes the gravitational interaction of all matter and that an observer's view of the universe does not depend on direction of observation or on location—make it possible to calculate physical conditions in the universe back to a very early time called the Planck time (after Max Planck). According to the model proposed by George Gamow in the 1940s, the universe expanded rapidly from a highly compressed early state, with a steady decrease in density and temperature. Within seconds, matter predominated over antimatter and certain nuclei formed. It took another million years before atoms could form and electromagnetic radiation could travel through space unimpeded. The abundances of hydrogen, helium, and lithium and the discovery of cosmic background radiation support the model, which also explains the redshifts of the light from distant galaxies as resulting from the expansion of space.

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or giant sequoia or Sierra redwood

Coniferous evergreen (Sequoiadendron giganteum; see conifer) found in scattered groves on the western slopes of the Sierra Nevada range of California, U.S. The largest of all trees in bulk, the big tree is distinguished from the coastal redwood (Sequoia sempervirens) by having uniformly scalelike, or awl-shaped, leaves that lie close against the branches, scaleless winter buds, and cones requiring two seasons to mature. The pyramidal tree shape, reddish brown furrowed bark, and drooping branches are common to both genera. The largest specimen (in total bulk) is the General Sherman tree in Sequoia National Park—101.5 ft (31 m) in circumference at its base, 272.4 ft (83 m) tall, and weighing an estimated 6,167 tons (5,593 metric tons). Because big-tree lumber is more brittle than redwood lumber and thus less desirable, the big tree has been easier to preserve; though some groves have been cut, most of the 70 remaining groves are now protected by state or national forests or parks.

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Preserve, southwestern Texas, U.S. It lies 250 mi (400 km) southeast of El Paso and occupies 1,252 sq mi (3,243 sq km). It was established in 1944 and named for the wide bend in the Rio Grande that skirts its southern edge. The park has magnificent mountain and desert scenery; it is home to more than 1,000 species of plants, and its wildlife includes coyotes, pumas, and roadrunners.

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Clock housed in the tower at the eastern end of Britain's Houses of Parliament. Designed by Sir Edmund Beckett (1816–1905), Big Ben is famous for its accuracy and its 13-ton bell. The name (for Sir Benjamin Hall, commissioner of works at the time of its installation in 1859) originally applied only to the bell but eventually came to include the clock itself.

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Big-endian may refer to:

• A philosophical viewpoint held by inhabitants of the island of Blefuscu from the book Gulliver's Travels by Jonathan Swift.
• Endianness, the byte ordering in memory used to represent some kind of data in computing.