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Pocket stereoscope with original test image. Used by military to examine stereoscopic pairs of aerial photographs . View of Boston , c. 1860 ; an early stereoscopic card for viewing a scene from nature Kaiser-Panorama consisted of a multi-station viewing apparatus and sets of stereo slides. Patented by A.
George Gordon Byron, 6th Baron Byron , later George Gordon Noel, 6th Baron Byron , FRS (22 January 1788 – 19 April 1824), commonly known simply as Lord Byron , was an English poet and a leading figure in the Romantic movement . Among Byron's best-known works are the lengthy narrative poems Don Juan and Childe Harold's Pilgrimage and the short lyric " She Walks in Beauty ." He is regarded as one of the greatest British poets and remains widely read and influential. He travelled to fight against the Ottoman Empire in the Greek War of Independence , for which Greeks revere him as a national hero . [ 1 ] He died at age 36 from a fever contracted while in Missolonghi in Greece.
General relativity , or the general theory of relativity , is the geometric theory of gravitation published by Albert Einstein in 1916 [ 1 ] and the current description of gravitation in modern physics . General relativity generalises special relativity and Newton's law of universal gravitation , providing a unified description of gravity as a geometric property of space and time , or spacetime . In particular, the curvature of spacetime is directly related to the energy and momentum of whatever matter and radiation are present. The relation is specified by the Einstein field equations , a system of partial differential equations .
Chaos theory is a field of study in mathematics , with applications in several disciplines including physics , engineering , economics , biology , and philosophy . Chaos theory studies the behavior of dynamical systems that are highly sensitive to initial conditions, an effect which is popularly referred to as the butterfly effect . Small differences in initial conditions (such as those due to rounding errors in numerical computation) yield widely diverging outcomes for such dynamical systems, rendering long-term prediction impossible in general. [ 1 ] This happens even though these systems are deterministic , meaning that their future behavior is fully determined by their initial conditions, with no random elements involved. [ 2 ] In other words, the deterministic nature of these systems does not make them predictable. [ 3 ] [ 4 ] This behavior is known as deterministic chaos, or simply chaos .
Schrödinger's cat: a cat, a flask of poison, and a radioactive source are placed in a sealed box. If an internal monitor detects radioactivity (i.e. a single atom decaying), the flask is shattered, releasing the poison that kills the cat. The Copenhagen interpretation of quantum mechanics implies that after a while, the cat is simultaneously alive and dead . Yet, when one looks in the box, one sees the cat either alive or dead, not both alive and dead. This poses the question of when exactly quantum superposition ends and reality collapses into one possibility or the other. Schrödinger's cat is a thought experiment , sometimes described as a paradox , devised by Austrian physicist Erwin Schrödinger in 1935.
The Bohr–Einstein debates were a series of public disputes about quantum mechanics between Albert Einstein and Niels Bohr , who were two of its founders. Their debates are remembered because of their importance to the philosophy of science . An account of the debates has been written by Bohr in an article titled "Discussions with Einstein on Epistemological Problems in Atomic Physics". [ 1 ] Despite their differences of opinion regarding quantum mechanics, Bohr and Einstein had a mutual admiration that was to last the rest of their lives. [ 2 ]
Rapid eye movement sleep ( REM sleep ) is a normal stage of sleep characterized by the rapid and random movement of the eyes . REM sleep is classified into two categories: tonic and phasic. [ 1 ] It was identified and defined by Nathaniel Kleitman , Eugene Aserinsky , and Jon Birtwell in the early 1950s. Criteria for REM sleep includes rapid eye movement, low muscle tone and a rapid, low-voltage EEG ; these features are easily discernible in a polysomnogram , [ 2 ] the sleep study typically done for patients with suspected sleep disorders. [ 3 ]
Wilhelm Richard Wagner ( pron.: / ˈ v ɑː ɡ n ər / ; German: [ˈʁiçaʁt ˈvaːɡnɐ] ; 22 May 1813 – 13 February 1883) was a German composer, theatre director, polemicist , and conductor primarily known for his operas (or, as some of his later works were later known, "music dramas"). His compositions, particularly those of his later period, are notable for their complex textures , rich harmonies and orchestration , and the elaborate use of leitmotifs —musical phrases associated with individual characters, places, ideas or plot elements. His advances in musical language, such as extreme chromaticism and quickly shifting tonal centres , greatly influenced the development of classical music ; his Tristan und Isolde is sometimes described as marking the start of modern music. Unlike most opera composers, Wagner wrote both the libretto and the music for each of his stage works.
The Holocaust (from the Greek ὁλόκαυστος holókaustos : hólos , "whole" and kaustós , "burnt") also known as the Shoah ( Hebrew : השואה , HaShoah , "catastrophe"; Yiddish : חורבן , Churben or Hurban , from the Hebrew for "destruction"), was the mass murder or genocide of approximately six million Jews during World War II , a programme of systematic state-sponsored murder by Nazi Germany , led by Adolf Hitler and the Nazi Party , throughout German-occupied territory. [ 4 ] Of the nine million Jews who had resided in Europe before the Holocaust, approximately two-thirds were killed. Over one million Jewish children were killed in the Holocaust, as were approximately two million Jewish women and three million Jewish men. A network of over 40,000 facilities in Germany and German-occupied territory were used to concentrate, hold, and kill Jews and other victims. [ 8 ]
Coordinates : Tsar Bomba ( Russian : Царь-бомба ; " Tsar Bomb") is the nickname for the AN602 hydrogen bomb , the most powerful nuclear weapon ever detonated. Its October 30, 1961 test remains the most powerful artificial explosion in human history. It was also referred to as Kuz'kina Mat' ( Russian : Кузькина мать , Kuzka's mother ), [ citation needed ] potentially referring to Nikita Khrushchev 's promise to show the United States a "Kuz'kina Mat'" at the 1960 United Nations General Assembly. The famous Russian idiom, which has been problematic for translators, equates roughly with the English “We’ll show you!”
The wheel was invented in the 4th millennium BC, and has become one of the world's most famous, and most useful technologies. This wheel is on display in The National Museum of Iran , in Tehran . The history of technology is the history of the invention of tools and techniques, and is similar in many ways to the history of humanity . Background knowledge has enabled people to create new things, and conversely, many scientific endeavors have become possible through technologies which assist humans to travel to places we could not otherwise go, and probe the nature of the universe in more detail than our natural senses allow.
The Indo-European languages are a family (or phylum ) of several hundred related languages and dialects . There are about 439 languages and dialects, according to the 2009 Ethnologue estimate, about half (221) belonging to the Indo-Aryan subbranch. [ 1 ] It includes most major current languages of Europe , the Iranian plateau , and Indian Subcontinent , and was also predominant in ancient Anatolia . With written attestations appearing since the Bronze Age in the form of the Anatolian languages and Mycenaean Greek , the Indo-European family is significant to the field of historical linguistics as possessing the longest recorded history after the Afro-Asiatic family .
Person of the Year (formerly Man of the Year ) is an annual issue of the United States newsmagazine Time that features and profiles a person, group, idea or object that "for better or for worse, ...has done the most to influence the events of the year." [ 1 ] [ edit ] History The tradition of selecting a Man of the Year began in 1927 with Time editors contemplating newsworthy stories possible during a slow news week. The idea was also an attempt to remedy the editorial embarrassment earlier that year of not having aviator Charles Lindbergh on its cover following his historic trans-Atlantic flight . By the end of the year, it was decided that a cover story featuring Lindbergh as the Man of the Year would serve both purposes. [ 2 ] Since then, individual people, classes of people, the computer (1982), and Planet Earth (1989) have all been selected for the special year-end issue.
Leviathan or The Matter, Forme and Power of a Common Wealth Ecclesiasticall and Civil — commonly referred to as Leviathan — is a book written by Thomas Hobbes (1588–1679) and published in 1651. Its name derives from the biblical Leviathan . The work concerns the structure of society and legitimate government, and is regarded as one of the earliest and most influential examples of social contract theory . [ 1 ] Leviathan ranks as a classic western work on statecraft comparable to Machiavelli 's The Prince . Written during the English Civil War (1642–1651), Leviathan argues for a social contract and rule by an absolute sovereign . Hobbes wrote that civil war and situations identified with a state of nature and the famous motto Bellum omnium contra omnes ("the war of all against all") could only be averted by strong central government. [ edit ] Content
The English Civil War (1642–1651) was a series of armed conflicts and political machinations between Parliamentarians ( Roundheads ) and Royalists ( Cavaliers ). The first (1642–46) and second (1648–49) civil wars pitted the supporters of King Charles I against the supporters of the Long Parliament , while the third war (1649–51) saw fighting between supporters of King Charles II and supporters of the Rump Parliament . The Civil War ended with the Parliamentary victory at the Battle of Worcester on 3 September 1651. The English Civil War led to the trial and execution of Charles I , the exile of his son, Charles II, and replacement of English monarchy with, first, the Commonwealth of England (1649–53), and then with a Protectorate (1653–59), under Oliver Cromwell 's personal rule. The monopoly of the Church of England on Christian worship in England ended with the victors consolidating the established Protestant Ascendancy in Ireland.