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Facts about Theory

Ptolemaic system. n. The astronomical system of Ptolemy, in which the earth is at the center of the universe with the sun, moon, planets, and stars revolving about it in circular orbits at increasing distance. Some of the orbits have epicycles.

A Brief History of Time: From the Big Bang to Black Holes is a popular-science book on cosmology (the study of the universe) by British physicist Stephen Hawking. ... He discusses two major theories, general relativity and quantum mechanics, that modern scientists use to describe the universe.

John Locke (1632–1704) is among the most influential political philosophers of the modern period. In the Two Treatises of Government, he defended the claim that men are by nature free and equal against claims that God had made all people naturally subject to a monarch.Nov 9, 2005

Charles Robert Darwin (February 12, 1809 to April 19, 1882) was a naturalist and biologist known for his theory of evolution and the process of natural selection.Dec 1, 2017