Russian Civil War
The Russian Civil War was a multi-party war in the former Russian Empire after the two Russian Revolutions of 1917, as many factions vied to determine Russia's political future. The two largest combatant groups were the Red Army, fighting for the Bolshevik form of socialism led by Vladimir Lenin, the loosely allied forces known as the White Army, which included diverse interests favouring political monarchism, economic capitalism and alternative forms of socialism, each with democratic and anti-democratic variants. In addition, rival militant socialists and non-ideological Green armies fought against both the Bolsheviks and the Whites. Eight foreign nations intervened against the Red Army, notably the former Allied military forces from the World War and the pro-German armies; the Red Army defeated the White Armed Forces of South Russia in Ukraine and the army led by Admiral Aleksandr Kolchak to the east in Siberia in 1919. The remains of the White forces commanded by Pyotr Nikolayevich Wrangel were beaten in Crimea and evacuated in late 1920.
Lesser battles of the war continued on the periphery for two more years, minor skirmishes with the remnants of the White forces in the Far East continued well into 1923. The war ended in 1923 in the sense that Bolshevik communist control of the newly formed Soviet Union was now assured, although armed national resistance in Central Asia was not crushed until 1934. There were an estimated 7,000,000–12,000,000 casualties during the war civilians; the Russian Civil War has been described by some as the greatest national catastrophe that Europe had yet seen. Many pro-independence movements emerged after the break-up of the Russian Empire and fought in the war. Several parts of the former Russian Empire—Finland, Latvia and Poland—were established as sovereign states, with their own civil wars and wars of independence; the rest of the former Russian Empire was consolidated into the Soviet Union shortly afterwards. After the abdication of Tsar Nicholas II of Russia, the Russian Provisional Government was established during the February Revolution of 1917.
Provisional Government was unable to solve the most pressing issues of the country, most to end the war with Central Powers, was overthrown by the Bolshevik wing of Russian Social Democratic Labour Party in the late 1917. From mid-1917 onwards, the Russian Army, the successor-organisation of the old Russian Imperial Army, started to disintegrate. In January 1918, after significant Bolshevik reverses in combat, the future People's Commissar for Military and Naval Affairs, Leon Trotsky headed the reorganization of the Red Guards into a Workers' and Peasants' Red Army in order to create a more effective fighting force; the Bolsheviks appointed political commissars to each unit of the Red Army to maintain morale and to ensure loyalty. In June 1918, when it had become apparent that a revolutionary army composed of workers would not suffice, Trotsky instituted mandatory conscription of the rural peasantry into the Red Army; the Bolsheviks overcame opposition of rural Russians to Red-Army conscription units by taking hostages and shooting them when necessary in order to force compliance the same practices used by the White Army officers.
The Red Army utilized former Tsarist officers as "military specialists". At the start of the civil war, former Tsarist officers comprised three-quarters of the Red Army officer-corps. By its end, 83% of all Red Army divisional and corps commanders were ex-Tsarist soldiers. While resistance to the Red Guard began on the day after the Bolshevik uprising, the Treaty of Brest-Litovsk and the instinct of one party rule became a catalyst for the formation of anti-Bolshevik groups both inside and outside Russia, pushing them into action against the new regime. A loose confederation of anti-Bolshevik forces aligned against the Communist government, including landowners, conservatives, middle-class citizens, pro-monarchists, army generals, non-Bolshevik socialists who still had grievances and democratic reformists voluntarily united only in their opposition to Bolshevik rule, their military forces, bolstered by forced conscriptions and terror as well as foreign influence, under the leadership of General Nikolai Yudenich, Admiral Alexander Kolchak and General Anton Denikin, became known as the White movement and controlled significant parts of the former Russian Empire for most of the war.
A Ukrainian nationalist movement was active in Ukraine during the war. More significant was the emergence of an anarchist political and military movement known as the Revolutionary Insurrectionary Army of Ukraine or the Anarchist Black Army led by Nestor Makhno; the Black Army, which counted numerous Jews and Ukrainian peasants in its ranks, played a key part in halting Denikin's White Army offensive towards Moscow during 1919 ejecting White forces from Crimea. The remoteness of the Volga Region, the Ural Region and the Far East was favorable for the anti-Bolshevik forces, the Whites set up a number of organizations in the cities of these regions; some of the military forces were set up on the basis of clandestine officers' organizations in the cities. The Czechoslovak Legions had been part of the Russian army and numbered around 30,000 troops by October 1917, they had an agreement with the new Bolshevik governmen
A mathematician is someone who uses an extensive knowledge of mathematics in his or her work to solve mathematical problems. Mathematics is concerned with numbers, quantity, space and change. One of the earliest known mathematicians was Thales of Miletus, he is credited with the first use of deductive reasoning applied to geometry, by deriving four corollaries to Thales' Theorem. The number of known mathematicians grew when Pythagoras of Samos established the Pythagorean School, whose doctrine it was that mathematics ruled the universe and whose motto was "All is number", it was the Pythagoreans who coined the term "mathematics", with whom the study of mathematics for its own sake begins. The first woman mathematician recorded by history was Hypatia of Alexandria, she succeeded her father as Librarian at the Great Library and wrote many works on applied mathematics. Because of a political dispute, the Christian community in Alexandria punished her, presuming she was involved, by stripping her naked and scraping off her skin with clamshells.
Science and mathematics in the Islamic world during the Middle Ages followed various models and modes of funding varied based on scholars. It was extensive patronage and strong intellectual policies implemented by specific rulers that allowed scientific knowledge to develop in many areas. Funding for translation of scientific texts in other languages was ongoing throughout the reign of certain caliphs, it turned out that certain scholars became experts in the works they translated and in turn received further support for continuing to develop certain sciences; as these sciences received wider attention from the elite, more scholars were invited and funded to study particular sciences. An example of a translator and mathematician who benefited from this type of support was al-Khawarizmi. A notable feature of many scholars working under Muslim rule in medieval times is that they were polymaths. Examples include the work on optics and astronomy of Ibn al-Haytham; the Renaissance brought an increased emphasis on science to Europe.
During this period of transition from a feudal and ecclesiastical culture to a predominantly secular one, many notable mathematicians had other occupations: Luca Pacioli. As time passed, many mathematicians gravitated towards universities. An emphasis on free thinking and experimentation had begun in Britain's oldest universities beginning in the seventeenth century at Oxford with the scientists Robert Hooke and Robert Boyle, at Cambridge where Isaac Newton was Lucasian Professor of Mathematics & Physics. Moving into the 19th century, the objective of universities all across Europe evolved from teaching the “regurgitation of knowledge” to “encourag productive thinking.” In 1810, Humboldt convinced the King of Prussia to build a university in Berlin based on Friedrich Schleiermacher’s liberal ideas. Thus and laboratories started to evolve. British universities of this period adopted some approaches familiar to the Italian and German universities, but as they enjoyed substantial freedoms and autonomy the changes there had begun with the Age of Enlightenment, the same influences that inspired Humboldt.
The Universities of Oxford and Cambridge emphasized the importance of research, arguably more authentically implementing Humboldt’s idea of a university than German universities, which were subject to state authority. Overall, science became the focus of universities in the 20th centuries. Students could conduct research in seminars or laboratories and began to produce doctoral theses with more scientific content. According to Humboldt, the mission of the University of Berlin was to pursue scientific knowledge; the German university system fostered professional, bureaucratically regulated scientific research performed in well-equipped laboratories, instead of the kind of research done by private and individual scholars in Great Britain and France. In fact, Rüegg asserts that the German system is responsible for the development of the modern research university because it focused on the idea of “freedom of scientific research and study.” Mathematicians cover a breadth of topics within mathematics in their undergraduate education, proceed to specialize in topics of their own choice at the graduate level.
In some universities, a qualifying exam serves to test both the breadth and depth of a student's understanding of mathematics. Mathematicians involved with solving problems with applications in real life are called applied mathematicians. Applied mathematicians are mathematical scientists who, with their specialized knowledge and professional methodology, approach many of the imposing problems presented in related scientific fields. With professional focus on a wide variety of problems, theoretical systems, localized constructs, applied mathematicians work in the study and formulation of mathematical models. Mathematicians and applied mathematicians are considered to be two of the STEM careers; the discipline of applied mathematics concerns
Orenburg is the administrative center of Orenburg Oblast, Russia. It lies on 1,478 kilometers southeast of Moscow, on the boundary of Europe and Asia. Orenburg is very close to the border with Kazakhstan. Population: 548,331; the city is in the basin of the middle current of the River Ural. The highest point of the city is 154.4 meters. Several historians have tried to explain the origins of the city's name, it was traditionally accepted. In all probability, the word combination "orenburg" was proposed by I. K. Kirillov, the founder of the city. In 1734, in accordance with his project, a package of governmental documents was worked out; this was the starting point for Orenburg as a fortress city near the place where the Or and the Ural rivers cross. On 7 June 1734, "A Privilege for Orenburg" was ordered by Empress Anna Ivanovna. While a construction site of the main fortress changed many times, the name "Orenburg" has not changed since its founding in 1743. Between 1938 and 1957, the city was referred to as Chkalov, named after the famous Soviet pilot Valery Chkalov, although he was not born in and never lived in Orenburg, never visited Orenburg.
In 1954, Chkalov's 5-meter bronze sculpture was erected on the occasion of his 50th birth anniversary. Orenburg was unofficially called the Asian capital of Russia. In 1734, the Russian Empire began expanding its control and influence in Asia starting from the construction of the fortress city called "Orenburg" on its eastern border. For this purpose, a settlement was founded here in 1735 - at the place where the Or and the Ural rivers cross; the initial site was chosen for settlement during the expedition of I. K. Kirilov, who initiated developmental activities in the region, he argued that the city was necessary "...for opening up transit routes to Bukhara, Bulk, to India", making it possible to receive "wealth from there — gold, lapis lazuli, garnet." After his death, a new administrator of the Orenburg expedition, Vasily Tatishchev, was appointed. He did not consider this place to be convenient for construction of the city, because it was flooded by the spring high waters; this encouraged to launch in 1739 preparations for building a new town with the old name downstream the river Ural on the mountain Krasnaya.
The old settlement was named the Orsk fortress. On 6 August 1741, the new town was founded. However, its construction did not start; the location on the mountain Krasnaya — treeless and remote from the river — was inappropriate for building the town. A new administrator of the Orenburg expedition, Ivan Neplyuyev, was appointed. On 19 April 1743, Orenburg was founded for a third time, on the compound, once the Berd fortress, 70 versts from the Krasnogorsk mountain area. In the summer of 1742, Neplyuev chose a new place surrounded by forests and crop fields, where the Yaik and the Sakmara rivers cross. Now it is the historical center of the city; the city built upon the mountain Krasnaya was named Krasnogorsk. Orenburg, was established by Ivan Neplyuyev in its present location 250 kilometers west down the Ural from Orsk in 1743; this third Orenburg has functioned as an important military outpost on the border with the nomadic Kazakhs. It became the center of the Orenburg Cossacks. Orenburg played a major role in Pugachev's Rebellion.
At the time, it was the seat of the governor. Yemelyan Pugachev besieged the city and its fortress from nearby Berda from October 1773 - March 26, 1774; the defense was organized by lieutenant-general Reinsdorp. General Golytsin defeated Pugachev at Berda, again at Kargala. Most of the city was left in ruins, thousands of inhabitants had died in the siege. Alexander Pushkin visited Orenburg in 1833 during a research trip for his books The History of Pugachev and his famous novel The Captain's Daughter, he met his friend Vladimir Dal here, who would write the first serious dictionary of the Russian language. Orenburg was the base for General Perovsky's expeditions against the Khanate of Khiva in the 1830s through 1850s. After the incorporation of Central Asia into the Russian Empire, Orenburg became a trading station and, since the completion of the Trans-Aral Railway, a prominent railway junction en route to the new Central Asian possessions and to Siberia. Orenburg functioned as the capital of the Kirghiz Autonomous Soviet Socialist Republic within Russia from 1920–1925.
When that republic was renamed Kazak Autonomous Soviet Socialist Republic in 1925, Orenburg joined Russia and Kyzylorda became the new capital. Almaty became the capital in 1929 after the construction of the Turkestan–Siberia Railway. Kazak Autonomous Soviet Socialist Republic was promoted to the union republic status as the Kazakh Soviet Socialist Republic Kazakh SSR in 1936. Orenburg remained in Russia. From 1938 to 1957, the city bore the name Chkalov; the city's distance from the German invasion during World War II led many Soviet enterprises to flee there, helping to spur the city's economic growth. Orenburg is the administrative center of the oblast and, within the framework of administrative divisions, it serves as
Crystallography is the experimental science of determining the arrangement of atoms in crystalline solids. The word "crystallography" derives from the Greek words crystallon "cold drop, frozen drop", with its meaning extending to all solids with some degree of transparency, graphein "to write". In July 2012, the United Nations recognised the importance of the science of crystallography by proclaiming that 2014 would be the International Year of Crystallography. X-ray crystallography is used to determine the structure of large biomolecules such as proteins. Before the development of X-ray diffraction crystallography, the study of crystals was based on physical measurements of their geometry; this involved measuring the angles of crystal faces relative to each other and to theoretical reference axes, establishing the symmetry of the crystal in question. This physical measurement is carried out using a goniometer; the position in 3D space of each crystal face is plotted on a stereographic net such as a Wulff net or Lambert net.
The pole to each face is plotted on the net. Each point is labelled with its Miller index; the final plot allows the symmetry of the crystal to be established. Crystallographic methods now depend on analysis of the diffraction patterns of a sample targeted by a beam of some type. X-rays are most used; this is facilitated by the wave properties of the particles. Crystallographers explicitly state the type of beam used, as in the terms X-ray crystallography, neutron diffraction and electron diffraction; these three types of radiation interact with the specimen in different ways. X-rays interact with the spatial distribution of electrons in the sample. Electrons are charged particles and therefore interact with the total charge distribution of both the atomic nuclei and the electrons of the sample. Neutrons are scattered by the atomic nuclei through the strong nuclear forces, but in addition, the magnetic moment of neutrons is non-zero, they are therefore scattered by magnetic fields. When neutrons are scattered from hydrogen-containing materials, they produce diffraction patterns with high noise levels.
However, the material can sometimes be treated to substitute deuterium for hydrogen. Because of these different forms of interaction, the three types of radiation are suitable for different crystallographic studies. An image of a small object is made using a lens to focus the beam, similar to a lens in a microscope. However, the wavelength of visible light is three orders of magnitude longer than the length of typical atomic bonds and atoms themselves. Therefore, obtaining information about the spatial arrangement of atoms requires the use of radiation with shorter wavelengths, such as X-ray or neutron beams. Employing shorter wavelengths implied abandoning microscopy and true imaging, because there exists no material from which a lens capable of focusing this type of radiation can be created. Scientists have had some success focusing X-rays with microscopic Fresnel zone plates made from gold, by critical-angle reflection inside long tapered capillaries. Diffracted X-ray or neutron beams cannot be focused to produce images, so the sample structure must be reconstructed from the diffraction pattern.
Sharp features in the diffraction pattern arise from periodic, repeating structure in the sample, which are very strong due to coherent reflection of many photons from many spaced instances of similar structure, while non-periodic components of the structure result in diffuse diffraction features - areas with a higher density and repetition of atom order tend to reflect more light toward one point in space when compared to those areas with fewer atoms and less repetition. Because of their ordered and repetitive structure, crystals give diffraction patterns of sharp Bragg reflection spots, are ideal for analyzing the structure of solids. Coordinates in square brackets such as denote a direction vector. Coordinates in angle brackets or chevrons such as <100> denote a family of directions which are related by symmetry operations. In the cubic crystal system for example, <100> would mean, or the negative of any of those directions. Miller indices in parentheses such as denote a plane of the crystal structure, regular repetitions of that plane with a particular spacing.
In the cubic system, the normal to the plane is the direction, but in lower-symmetry cases, the normal to is not parallel to. Indices in curly brackets or braces such as denote a family of planes and their normals which are equivalent in cubic materials due to symmetry operations, much the way angle brackets denote a family of directions. In non-cubic materials, <hkl> is not perpendicular to. Some materials that have been analyzed crystallographically, such as proteins, do not occur as crystals; such molecules are placed in solution and allowed to crystallize through vapor diffusion. A drop of solution containing the molecule and precipitants is sealed in a container with a reservoir containing a hygroscopic solution. Water in the drop diffuses to the reservoir increasing the concentration and allowing a crystal to form. If the concentration were to rise more the molecule would precipitate out of solution, resulting in disorderly granules rather than an orderly and hence usable crystal. Once a crystal is obtained, data can be collected using a beam of radiation.
Although many universities that engage in crystallographic research have their own X-ray producing equipment, synchrotrons are used as X-ray sources, bec
Edgar T. Wherry
Edgar Theodore Wherry was an American mineralogist, soil scientist and botanist. He had a deep interest in Sarracenia. Wherry earned his bachelor's degree in chemistry in 1906 from the University of Pennsylvania, he received his doctorate in mineralogy in 1909 from the same university. From 1908 to 1912, he taught at Lehigh University, he lived in Washington, D. C. from 1912 to 1930, part of this time working as an assistant curator of mineralogy for the U. S. National Museum, for the Bureau of Chemistry of the United States Department of Agriculture, he taught botany at the University of Pennsylvania from 1930 to 1955. He wrote many papers in mineralogy through those years, he was the fourth president of the Mineralogical Society of America in 1923, he became interested in ferns at age 30, did much work in that field the rest of his life. He was president of the American Fern Society from 1934 to 1939, he wrote three key guides to the ferns of eastern North America. The first was Guide to Eastern Ferns in 1937, followed by a updated The Fern Guide in 1961, lastly The Southern Fern Guide in 1964.
He was in the forefront of taxonomic work on ferns, his field guides provided far more current taxonomy than other guides of the day. He donated all royalties from the fern field guides to the American Fern Society. In 1964, he was awarded the Mary Soper Pope Memorial Award in botany; the "Edgar T. Wherry Award" was established in 1989 by the Botanical Society of America for the best paper presented each year in the pteridological section. Asplenium × wherryi D. M. Smith Castilleja wherryana Pennell Dryopteris × neo-wherryi Wagner Dryopteris wherryi Small Iris wherryana Crane Mimosa wherryana Standl. Mimosopsis wherryana Britton Penstemon wherryi Pennell Phlox wherryi Heath Silene wherryi Small Wherry authored 109 plant taxon names, coauthored another 11. Additionally, he made 223 combinations based on pre-existing names. Following are a few examples. Asplenium x trudellii Wherry Microgramma heterophylla Wherry Sarracenia oreophila Wherry Sarracenia jonesii Wherry Wherry, Edgar T. Wild Flowers of Mount Desert Island, Maine.
Garden Club of Mount Desert, Bar Harbor, Maine. 1928. 164 pp. ill. Wherry, Edgar T; the Wild Flower Guide and Midland United States. Doubleday, Garden City, New York. 1948. 202 pp. ill. Wherry, Edgar T. Guide to Eastern Ferns. Illustrated with line drawings by Oliver Stoner and Cyrus Feldman. First edition: The Science Press Printing Company, Pennsylvania. 1937. Iv, 220 pp. frontispiece, illus, 6.5x4in, hardcover. Second edition: University of Pennsylvania Press, Pennsylvania. 1942. Iv, 252 pp. hardcover. Reprint of second edition: University of Pennsylvania Press, Pennsylvania. 1948. Iv,252 pp. hardcover. Wherry, Edgar T; the Genus Phlox. 174 p. illus. Morris Arboretum Monograph 3. 1955. 174 pp. ill. Wherry, Edgar T; the Fern Guide. Illustrated by James C. W. Chen. First printing: Doubleday & Co. Garden City, New York. 1961. 318 pp. hardcover. Reprint: Dover Publications Inc. New York, New York. 1994. 318 pp. 120 b/w softcover. ISBN 0-486-28496-4. Wherry, Edgar T; the Southern Fern Guide. Illustrated by James C. W. Chen and Keith C. Y.
Chen. First edition: Doubleday & Co. Garden City, New York. 1964. 349 pp. hardcover. Second edition: "Corrected First Edition with Nomenclatural Changes". American Fern Society, New York Chapter, New York. 1972. 349 pp. softcover. LC 77-93190. Reprint of second edition: American Fern Society, New York Chapter, New York. 1978. 349 pp. hardcover. Hooker and Arthur Montgomery. "Edgar Theodore Wherry." American Mineralogist 60:533-539. 1975: http://www.minsocam.org/ammin/AM60/AM60_533.pdf Fogg, John M. Jr. "Edgar Wherry in Pennsylvania." American Fern Journal 66:33- 1976. Wagner, Warren H. Jr. "Edgar T. Wherry and his contributions to pteridology." American Fern Journal 73:1- 1983
Russian Soviet Federative Socialist Republic
The Russian Soviet Federative Socialist Republic known as the Russian Soviet Republic and the Russian Socialist Federative Soviet Republic, as well as being unofficially known as the Russian Federation, Soviet Russia, or Russia, was an independent state from 1917 to 1922, afterwards the largest, most populous and most economically developed of the 15 Soviet socialist republics of the Soviet Union from 1922 to 1990 a sovereign part of the Soviet Union with priority of Russian laws over Union-level legislation in 1990 and 1991, during the last two years of the existence of the USSR. The Russian Republic comprised sixteen smaller constituent units of autonomous republics, five autonomous oblasts, ten autonomous okrugs, six krais and forty oblasts. Russians formed the largest ethnic group; the capital of the Russian SFSR was Moscow and the other major urban centers included Leningrad, Yekaterinburg, Nizhny Novgorod and Samara. The economy of Russia became industrialized, accounting for about two-thirds of the electricity produced in the USSR.
By 1961, it was the third largest producer of petroleum due to new discoveries in the Volga-Urals region and Siberia, trailing in production to only the United States and Saudi Arabia. In 1974, there were 475 institutes of higher education in the republic providing education in 47 languages to some 23,941,000 students. A network of territorially organized public-health services provided health care. After 1985, the "perestroika" restructuring policies of the Gorbachev administration liberalised the economy, which had become stagnant since the late 1970s under General Secretary Leonid Brezhnev, with the introduction of non-state owned enterprises such as cooperatives; the Russian Soviet Republic was proclaimed on 7 November 1917 as a sovereign state and the world's first constitutionally socialist state with the ideology of Communism. The first Constitution was adopted in 1918. In 1922, the Russian SFSR signed the Treaty on the Creation of the USSR setting up of the Union of Soviet Socialist Republics.
The 1977 Soviet Constitution stated that "Union Republic is a sovereign state that has united in the Union" and "each Union Republic shall retain the right to secede from the USSR". On 12 June 1990, the Congress of People's Deputies adopted the Declaration of State Sovereignty, established separation of powers, established citizenship of Russia and stated that the RSFSR shall retain the right of free secession from the USSR. On 12 June 1991, Boris Yeltsin, supported by the Democratic Russia pro-reform movement, was elected the first and only President of the RSFSR, a post that would become the presidency of the Russian Federation; the August 1991 Soviet coup d'état attempt with the temporary brief internment of President Mikhail Gorbachev destabilised the Soviet Union. On 8 December 1991, the heads of Russia and Belarus signed the Belavezha Accords; the agreement declared dissolution of the USSR by its original founding states and established the Commonwealth of Independent States as a loose confederation.
On 12 December, the agreement was ratified by the Supreme Soviet. On 25 December 1991, following the resignation of Gorbachev as President of the Soviet Union, the Russian SFSR was renamed the Russian Federation, with President Yeltsin re-establishing the sovereign and independent state. With the lowering at 12 midnight of the red flag with hammer and sickle design of the now former USSR from the towers of the Kremlin in Moscow on 26 December 1991, the USSR was self-dissolved by the Soviet of the Republics, which by that time was the only functioning chamber of the parliamentary Supreme Soviet. After dissolution of the USSR, Russia declared that it assumed the rights and obligations of the dissolved central Soviet government, including UN membership and permanent membership on the Security Council, but excluding foreign debt and foreign assets of the USSR; the 1978 RSFSR Constitution was amended several times to reflect the transition to democracy, private property and market economy. The new Russian Constitution, coming into effect on 25 December 1993 after a constitutional crisis abolished the Soviet form of government and replaced it with a semi-presidential system.
Under the leadership of Vladimir Lenin and Leon Trotsky, the Bolshevik communists established the Soviet state on 7 November 1917 after the interim Russian Provisional Government, most led by opposing democratic socialist Alexander Kerensky, which governed the new Russian Republic after the overthrow of the Russian Empire government of the Romanov imperial dynasty of Czar Nicholas II the previous March, was now itself overthrown during the following October Revolution, the second of t
Space is the boundless three-dimensional extent in which objects and events have relative position and direction. Physical space is conceived in three linear dimensions, although modern physicists consider it, with time, to be part of a boundless four-dimensional continuum known as spacetime; the concept of space is considered to be of fundamental importance to an understanding of the physical universe. However, disagreement continues between philosophers over whether it is itself an entity, a relationship between entities, or part of a conceptual framework. Debates concerning the nature and the mode of existence of space date back to antiquity. Many of these classical philosophical questions were discussed in the Renaissance and reformulated in the 17th century during the early development of classical mechanics. In Isaac Newton's view, space was absolute—in the sense that it existed permanently and independently of whether there was any matter in the space. Other natural philosophers, notably Gottfried Leibniz, thought instead that space was in fact a collection of relations between objects, given by their distance and direction from one another.
In the 18th century, the philosopher and theologian George Berkeley attempted to refute the "visibility of spatial depth" in his Essay Towards a New Theory of Vision. The metaphysician Immanuel Kant said that the concepts of space and time are not empirical ones derived from experiences of the outside world—they are elements of an given systematic framework that humans possess and use to structure all experiences. Kant referred to the experience of "space" in his Critique of Pure Reason as being a subjective "pure a priori form of intuition". In the 19th and 20th centuries mathematicians began to examine geometries that are non-Euclidean, in which space is conceived as curved, rather than flat. According to Albert Einstein's theory of general relativity, space around gravitational fields deviates from Euclidean space. Experimental tests of general relativity have confirmed that non-Euclidean geometries provide a better model for the shape of space. Galilean and Cartesian theories about space and motion are at the foundation of the Scientific Revolution, understood to have culminated with the publication of Newton's Principia in 1687.
Newton's theories about space and time helped. While his theory of space is considered the most influential in Physics, it emerged from his predecessors' ideas about the same; as one of the pioneers of modern science, Galilei revised the established Aristotelian and Ptolemaic ideas about a geocentric cosmos. He backed the Copernican theory that the universe was heliocentric, with a stationary sun at the center and the planets—including the Earth—revolving around the sun. If the Earth moved, the Aristotelian belief that its natural tendency was to remain at rest was in question. Galilei wanted to prove instead that the sun moved around its axis, that motion was as natural to an object as the state of rest. In other words, for Galilei, celestial bodies, including the Earth, were inclined to move in circles; this view displaced another Aristotelian idea—that all objects gravitated towards their designated natural place-of-belonging. Descartes set out to replace the Aristotelian worldview with a theory about space and motion as determined by natural laws.
In other words, he sought a metaphysical foundation or a mechanical explanation for his theories about matter and motion. Cartesian space was Euclidean in structure—infinite and flat, it was defined as that. The Cartesian notion of space is linked to his theories about the nature of the body and matter, he is famously known for his "cogito ergo sum", or the idea that we can only be certain of the fact that we can doubt, therefore think and therefore exist. His theories belong to the rationalist tradition, which attributes knowledge about the world to our ability to think rather than to our experiences, as the empiricists believe, he posited a clear distinction between the body and mind, referred to as the Cartesian dualism. Following Galilei and Descartes, during the seventeenth century the philosophy of space and time revolved around the ideas of Gottfried Leibniz, a German philosopher–mathematician, Isaac Newton, who set out two opposing theories of what space is. Rather than being an entity that independently exists over and above other matter, Leibniz held that space is no more than the collection of spatial relations between objects in the world: "space is that which results from places taken together".
Unoccupied regions are those that could have objects in them, thus spatial relations with other places. For Leibniz space was an idealised abstraction from the relations between individual entities or their possible locations and therefore could not be continuous but must be discrete. Space could be thought of in a similar way to the relations between family members. Although people in the family are related to one another, the relations do not exist independently of the people. Leibniz argued that space could not exist independently of objects in the world because that implies a difference between two universes alike except for the location of the material world in