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    Anonymous
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    Nikolai Ivanovich Lobachevsky (Russian: Никола́й Ива́нович Лобаче́вский) (December 1, 1792 – February 24, 1856) was a Russian mathematician and geometer, renowned primarily for his pioneering works on hyperbolic geometry, otherwise known as Lobachevskian geometry. William Kingdon Clifford called Lobachevsky the "Copernicus of Geometry" due to the revolutionary character of his work.

    Nikolai Ivanovich Lobachevsky's father Ivan Maksimovich Lobachevsky, worked as a clerk in an office which was involved in land surveying while Nikolai Ivanovich's mother was Praskovia Alexandrovna Lobachevskaya. Nikolai Ivanovich was one of three sons in this poor family. When Nikolai Ivanovich was seven years of age his father died and, in 1800, his mother moved with her three sons to the city of Kazan in western Russia on the edge of Siberia. There the boys attended Kazan Gymnasium, financed by government scholarships, with Nikolai Ivanovich entering the school in 1802.

    In 1807 Lobachevsky graduated from the Gymnasium and entered Kazan University as a free student. Kazan State University had been founded in 1804, the result of one of the many reforms of the emperor Alexander I, and it opened in the following year, only two years before Lobachevsky began his undergraduate career. His original intention was to study medicine but he changed to study a broad scientific course involving mathematics and physics. Vinberg writes:

    One of the excellent professors who had been invited from Germany was Martin Bartels (1769 – 1833) who had been appointed as Professor of Mathematics. Bartels was a school teacher and friend of Gauss, and the two corresponded. We shall return later to discuss ideas of some historians, for example M Kline, that Gauss may have given Lobachevsky hints regarding directions that he might take in his mathematical work through the letters exchanged between Bartels and Gauss. A skilled teacher, Bartels soon interested Lobachevsky in mathematics. We do know that Bartels lectured on the history of mathematics and that he gave a course based on the text by Montucla. Since Euclid's Elements and his theory of parallel lines are discussed in detail in Montucla's book, it seems likely that Lobachevsky's interest in the Fifth Postulate was stimulated by these lectures. Laptev has established that Lobachevsky attended this history course given by Bartels.

    Lobachevsky received a Master's Degree in physics and mathematics in 1811. In 1814 he was appointed to a lectureship and in 1816 he became an extraordinary professor. In 1822 he was appointed as a full professor. Lobachevsky had experienced difficulties during this period at the University of Kazan.  Despite these difficulties, many brought on according to Vinberg in [44] by Lobachevsky's "upright and independent character", he achieved many things. As well as his vigorous mathematical research, which we shall talk about later in this article, he taught a wide range of topics including mathematics, physics and astronomy. His lectures were detailed and clear, so that they could be understood even by poorly prepared students.

    Lobachevsky bought equipment for the physics laboratory, and he purchased books for the library in St Petersburg. He was appointed to important positions within the university such as the dean of the Mathematics and Physics Department between 1820 and 1825 and head librarian from 1825 to 1835. He also served as Head of the Observatory and was clearly strongly influencing policy within the University. However  the clashes with the curator (Magnitskii) continued.

    In 1826 Tsar Nicholas I became ruler and introduced a more tolerant regime. In that year Magnitskii was dismissed as curator of Kazan University and a new curator M N Musin-Pushkin was appointed. The atmosphere now changed markedly and Musin-Pushkin found in Lobachevsky someone who could work with him in bringing important changes to the university. In 1827 Lobachevsky became rector of Kazan University, a post he was to hold for the next 19 years. The following year he made a speech (which was published in 1832) On the most important subjects of education and this gives clearly what were the ideas in his educational philosophy.

    The University of Kazan flourished while Lobachevsky was rector, and this was largely due to his influence. There was a vigorous programme of new building, with a library, an astronomical observatory, new medical facilities and physics, chemistry and anatomy laboratories being constructed. He pressed strongly for higher levels of scientific research and he equally encouraged research in the arts, particularly developing a leading centre for Oriental Studies. There was a marked increase in the number of students and Lobachevsky invested much effort in raising not only the standards of education in the university, but also in the local schools.

    Two natural disasters struck the university while he was Rector of Kazan:  the cholera epidemic in 1830 and a big fire in 1842. Owing to resolute and reasonable measures taken by Lobachevsky the damage to the University was reduced to a minimum. for his activity during the cholera epidemic Lobachevsky received a message of thanks from the Emperor.

    Despite this heavy administrative load, Lobachevsky continued to teach a variety of different topics such as mechanics, hydrodynamics, integration, differential equations, the calculus of variations, and mathematical physics. He even found time to give lectures on physics to the general public during the years 1838 to 1840 but the heavy work-load was to eventually take its toll on his health.

    In 1832 Lobachevsky married Lady Varvara Alexejevna Moisieva who came from a wealthy family. At the time of his marriage his wife was a young girl while Lobachevsky was forty years old. The marriage gave them seven children.

    After Lobachevsky retired in 1846 (essentially dismissed by the University of Kazan), his health rapidly deteriorated. Matveev in his article quotes many records concerning Lobachevsky's estate which he purchased at Slobodka. There are many claims by biographers that Lobachevsky was an impractical manager who jeopardised his financial position by purchasing the estate while living on a pension; that he had no time to look after the estate and took little interest in it; that he was left in poverty and ignored by the local officials, etc.

    But Matveev shows that these claims are totally unjustified. Soon after he retired, however, his favourite eldest son died and Lobachevsky was hit hard by this tragedy. The illness that he suffered from became progressively worse and led to blindness. These and financial difficulties added to the heavy burdens he had to bear over his last years. His great mathematical achievements, which we shall now discuss, were not recognised in his lifetime and he died without having any notion of the fame and importance that his work would achieve.

    Since Euclid's axiomatic formulation of geometry mathematicians had been trying to prove his fifth postulate as a theorem deduced from the other four axioms. The fifth postulate states that given a line and a point not on the line, a unique line can be drawn through the point parallel to the given line. Lobachevsky did not try to prove this postulate as a theorem. Instead he studied geometry in which the fifth postulate does not necessarily hold. Lobachevsky categorised euclidean as a special case of this more general geometry.

    His major work, Geometriya completed in 1823, was not published in its original form until 1909. On 11 February 1826, in the session of the Department of Physico-Mathematical Sciences at Kazan University, Lobachevsky requested that his work about a new geometry was heard and his paper A concise outline of the foundations of geometry was sent to referees. The text of this paper has not survived but the ideas were incorporated, perhaps in a modified form, in Lobachevsky's first publication on hyperbolic geometry. He published this work on non-euclidean geometry, the first account of the subject to appear in print, in 1829. It was published in the Kazan Messenger but rejected by Ostrogradski when it was submitted for publication by the St Petersburg Academy of Sciences.

    In 1834 Lobachevsky found a method for the approximation of the roots of algebraic equations. This method of numerical solution of algebraic equations, developed independently by Gräffe to answer a prize question of the Berlin Academy, is today a particularly suitable method for using computers to solve such problems. This method is today called the Dandelin-Gräffe method since Dandelin also independently investigated it, but only in Russia does the method appear to be named after Lobachevsky who is the third independent discoverer.

    In 1837 Lobachevsky published his article Géométrie imaginaire and a summary of his new geometry Geometrische Untersuchungen zur Theorie der Parellellinien was published in Berlin in 1840. This last publication greatly impressed Gauss but much has been written about Gauss's role in the discovery of non-euclidean geometry which is just simply false. There is a coincidence which arises from the fact that we know that Gauss himself discovered non-euclidean geometry but told very few people, only his closest friends. Two of his friends were Farkas Bolyai, the father of János Bolyai (an independent discoverer of non-euclidean geometry), and Bartels who was Lobachevsky's teacher. This coincidence has prompted speculation that both Lobachevsky and Bolyai were led to their discoveries by Gauss. M. Kline has put forward this theory but it has been refuted in several works. Also Laptev has examined the correspondence between Bartels and Gauss and shown that Bartels did not know about Gauss's results in non-euclidean geometry.

    The story of how Lobachevsky's hyperbolic geometry came to be accepted is a complex one and this biography is not the place in which to go into details, but we shall note the main events. In 1866, ten years after Lobachevsky's death, Hoüel published a French translation of Lobachevsky's Geometrische Untersuchungen together with some of Gauss's correspondence on non-euclidean geometry. Beltrami, in 1868, gave a concrete realisation of Lobachevsky's geometry. Weierstrass led a seminar on Lobachevsky's geometry in 1870 which was attended by Klein and, two years later, after Klein and Lie had discussed these new generalisations of geometry in Paris, Klein produced his general view of geometry as the properties invariant under the action of some group of transformations in the Erlanger Programm. There were two further major contributions to Lobachevsky's geometry by Poincaré in 1882 and 1887. Perhaps these finally mark the acceptance of Lobachevsky's ideas which would eventually be seen as vital steps in freeing the thinking of mathematicians so that relativity theory had a natural mathematical foundation

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    #401904

    Anonymous

    Лобачевский Николай Иванович [20.11(1.12).1792, Нижний Новгород, – 12(24).2.1856, Казань], русский математик, создатель неевклидовой геометрии, мыслитель-материалист, деятель университетского образования и народного просвещения. Родился в семье мелкого чиновника. Почти всю жизнь Лобачевский провел в Казани. Там он учился в Казанском университете (1807–11). Рано обнаружил выдающиеся способности, по окончании университета получил степень магистра (1811) и был оставлен при университете; в 1814 стал адъюнктом, в 1816 – экстраординарным и в 1822 – ординарным профессором. Несмотря на реакционную обстановку, сложившуюся в годы попечительства М. Л. Магницкого, Лобачевский вел напряженную научную и педагогическую работу (преподавал математику, физику и астрономию), закупил в столице оборудование для физического кабинета и книги для библиотеки, а затем возглавлял ее 10 лет (с 1825); Лобачевский заведовал обсерваторией; избирался деканом физико-математического факультета (1820–22, 1823–25). Но столкновения с попечителем обострились: Лобачевский отстаивал в преподавании научные материалистические взгляды.

    В эти годы Лобачевский отыскивал пути строгого построения начал геометрии. Сохранились: студенческие записи его лекций (от 1817), где им делалась попытка доказать постулат параллельности Евклида, но в рукописи учебника «Геометрия» (1823) он уже отказался от этой попытки. В «Обозрениях преподавания чистой математики» в 1822–23 и 1824–25 Лобачевский указал на «до сих пор непобедимую» трудность проблемы параллелизма и на необходимость принимать в геометрии в качестве исходных понятия, непосредственно приобретаемые из природы. Наконец, преодолев тысячелетние традиции, он приходит к созданию новой геометрии – так называемой «геометрии Лобачевского». 7 февраля 1826 он представил для напечатания в Записках физико-математического отделения сочинение «Сжатое изложение начал геометрии со строгим доказательством теоремы о параллельных» (на французском языке). Но издание не осуществилось. Рукопись и отзывы не сохранились, однако само сочинение было включено Лобачевским в его труд «О началах геометрии» в журнале «Казанский вестник» (1829–30), явившийся первой в мировой литературе публикацией по неевклидовой геометрии. Исходя из поисков безусловной строгости и ясности в началах геометрии, Лобачевский рассматривает аксиому параллельности Евклида как произвольное ограничение, как требование слишком жесткое, ограничивающее возможности теории, описывающей свойства пространства. Он заменяет эту аксиому требованием более широким и общим, а именно: на плоскости через точку, не лежащую на данной прямой, проходит более чем одна прямая, не пересекающая данную (по существу не менее чем одна, если учесть предельный случай).

    Разработанная Лобачевским новая геометрия существенно отличается от евклидовой геометрии, но при больших значениях входящей в формулы некоторой постоянной R (радиус кривизны пространства) отклонение становится незначительным.

    В соответствии со своим материалистическим подходом к изучению природы, Лобачевский полагал, что только научный опыт может выявить, какая из геометрий осуществляется в физическом пространстве. Используя новейшие астрономические данные того времени, он пришел к выводу, что число R очень велико и отклонения от евклидовой геометрии если и существуют, то заключены в пределах ошибок измерений, то есть была обоснована практическая пригодность евклидовой геометрии. Кроме того, Лобачевский показал, как его геометрию можно применять в других разделах математики, а именно в математическом анализе при вычислении определенных интегралов.

    Доклад Лобачевского совпал по времени с увольнением Магницкого. Лобачевского избрали ректором (1827) и за 19 лет руководства университетом он добился его подлинного расцвета. Программа деятельности Лобачевского отражена в его замечательной речи «О важнейших предметах воспитания» (1828, опубликована 1832), в которой обрисован идеал гармонического развития личности, подчеркнуто общественное значение воспитания и образования, освещена роль наук и долг ученого перед страной и народом.

    В бытность Лобачевского ректором было осуществлено в 1832–40 строительство целого комплекса вспомогательных зданий: библиотека, астрономическая обсерватория, физический кабинет и химическая лаборатория, анатомический театр, клиника и др. Он положил начало «Ученым запискам Казанского университета» (1834) и развил издательскую деятельность. Уровень научно-учебной работы повысился, контингент студентов возрос, университет стал важным центром востоковедения. Немало сил Лобачевский вкладывал и в улучшение постановки преподавания в гимназиях и училищах округа. В моменты стихийных бедствий (эпидемия холеры в 1830, пожар Казани в 1842) особенно ярко проявилась его забота об университете. Но ректорство не отрывало Лобачевского от преподавания: в разные годы он читал лекции по аналитической механике, гидромеханике, интегральному исчислению, дифференциальным уравнениям, математической физике, вариационному исчислению, а в 1838–40 – научно-популярные лекции по физике для населения. Студенты высоко ценили лекции Лобачевского.

    Однако научные идеи Лобачевского не были поняты современниками. Его труд «О началах геометрии», представленный в 1832 советом университета в Академию наук, получил у М. В. Остроградского отрицательную оценку, а в 1834 в реакции журнала «Сын отечества» появилась анонимная издевательская статейка. Но Лобачевский не прекратил разработки своей геометрии. Его работы появлялись в 1835–38, а в 1840 в Германии вышла его книга «Геометрические исследования» (на немецком языке). Эта стойкая борьба за научную истину отличает Лобачевского от двух его современников, тоже пришедших к открытию неевклидовой геометрии. Венгерский математик Я. Больяй опубликовал свой труд позднее Лобачевского (1832). Не встретив поддержки у современников, он не продолжил исследований. Немецкий математик К. Ф. Гаусс также владел началами неевклидовой геометрии. Но из опасения встретить непонимание Гаусс не разрабатывал их далее и не опубликовал. Однако, не высказываясь в печати, он высоко оценил труды Лобачевского, и по его предложению Лобачевский был в 1842 избран членом-корреспондентом Геттингенского ученого общества.

    Лобачевский получил ряд ценных результатов и в других разделах математики: так, в алгебре он разработал новый метод приближенного решения уравнений («Лобачевского метод»), в математическом анализе получил ряд тонких теорем о тригонометрических рядах, уточнил понятие непрерывной функции и др.

    В 1846 Лобачевский оказался фактически отстраненным от университета. Он был назначен помощником нового попечителя (без оплаты) и лишен ректорства. Здоровье его пошатнулось. Но семейное горе – смерть сына, материальные затруднения и развивавшаяся слепота не могли сломить мужества Лобачевского. Последнюю работу «Пангеометрию» он создал за год до смерти, диктуя ее текст.

    Лобачевский умер непризнанным. Большую роль в признании трудов Лобачевского сыграли исследования Э. Бельтрами (1868), Ф. Клейна (1871), А. Пуанкаре (1883) и др. Казанский университет и физико-математическое общество провели большую работу по выявлению значения идей Лобачевского и изданию его геометрических сочинений. Широкое признание пришло к 100-летнему юбилею Лобачевского – была учреждена международная премия, в Казани открыт памятник (1896).

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    #401905

    Anonymous

    Great thread about a brilliant, albeit very underrated man.

    It would seem that in the end he outwitted both Euclid (well no surprise here) and Riemann, since the most likely scenario is that we are in an hyperbolic universe.

    #401906

    Anonymous

    Mathematics, Physics and Technical sciences were and still are somewhat neglected or taught badly in most of Slavic countries

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