Bernoulli, Jakob

Like dynasties monarchs, there was a famous dynasty of scientists Bernoulli - they even named as the Kings: Jacob I, Johann I, Daniel I... These three - mathematics and mechanics - have won the greatest fame. Settled in the Swiss city of Basel, Nicholas Bernoulli selling pharmaceutical products and medicinal herbs. He enjoyed considerable respect for fellow citizens: he was a member of the Grand Council of the City and the Court. He had 11 children among them - Jakob and Johann.

The eldest of the brothers Jakob I Bernoulli (1654-1705) studied at the University of Basel philosophy and theology, knew many languages, but decided to devote himself to mathematics, which worked independently. According to the custom of young men of the time after graduation he went to travel, served as a tutor in Genoa, and from 1683 began to read lectures on experimental physics in Basel, where he later became a professor of mathematics. His lectures were listened to his brother Johann, a nephew of Nicholas, a future member of the St. Petersburg Academy of Sciences of the mathematician and engineer J. Herman, the father of the future of the great mathematician Paul Euler.

Once attracted the attention of Jacob Bernoulli's paper Leibniz in the journal Proceedings of the scientists' for 1684 on the new differential calculus. Jacob turned to the author of the letter, wishing to find obscure places in the article, but a German scientist got it a few years. During this time, the brothers Jakob and Johann themselves understood the intricacies of the new calculus. Then Johann told Leibniz that, . that posed the problem of Brachistochrone curve (the curve of steepest descent): 'By what trajectory should move in a vertical plane under gravity material point, . that the path from point A to point B in the shortest time to go? " Leibniz replied, . that 'this problem was fascinated with its beauty as well, . it used to be fascinated by the apple Eve ',
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He advised Johann publish it to wittiest of mathematics for the year were able to give its decision. Johann did so. The solution offered three: Jakob Bernoulli, French mathematician Marquis l'HцЄpital and the one who wished to remain anonymous, printed response in the British journal anonymous. In vain, it 'learned of a lion by his claws' - Newton. However, the best option was Jacob. Johann Bernoulli formulated and the problem of the curve, representing the shortest distance between two points on a given surface - the geodesic line.

Jakob Bernoulli belong significant achievements in the theory of series, differential calculus and number theory, where his name among some specific properties. But the main merit of the scientist in that he formulated and proved a special case of the most important theorems of probability theory - the law of large numbers. It was published after the death of Jakob Bernoulli in his book 'The Art of assumptions' (1713). After 200 years, the portion of the book that belonged to the law of large numbers, has been translated into Russian YV Uspensky and published in St. Petersburg under the editorship of academician AA Markov.

Johann I Bernoulli (1667-1748) after graduating from university was awarded the title of licentiate of medicine, but took up mathematics, showed with a brilliant. While in Paris, he gave several lectures on differential calculus Marquis l'HцЄpital, which, without the consent of the author and published them as 'Course Analysis' in 1696. This book is introduced by European scientists with the ideas of differential calculus. In 1694, Johann Bernoulli in Basel, he defended his doctoral dissertation in medicine on the theme 'On the motion of the muscles', which was based on the mathematical analysis.

Soon Johann married. MAZ service in Basel, he was unable to because 10 years has lectured on experimental physics and mathematics in the Dutch city of Groningen. After the death of Jakob Bernoulli, Johann took the chair of mathematics at Basel. His works are included in the differential and integral calculus, calculus of variations and their applications, theory of vibrations of the string and pendulum impact theory. Biographers have pointed out the bad character of Johann Bernoulli. He is very sensitive about everything that concerned the priority of discoveries, and often argued about this with his brother Jacob, and the Marquis de l'HцЄpital, and her son Daniel. He also took part in the debate about who is first, Leibniz or Newton created the calculus of the infinitesimal. The only mathematician, to whom he had not presented any claims, was his pupil Leonhard Euler, talent and effort we eventually got all the more appreciated. Johann Bernoulli I was a foreign member of the Paris Academy of Sciences, the Berlin Scientific Society, Royal Society of London, St. Petersburg Academy of Sciences.

Was famous as a mathematician and engineer, his son Daniel I Bernoulli (1700-1782). He was born in Groningen. After graduating from the University of Basel has received the degree of Doctor of Philosophy and Doctor of Medicine, was engaged in practical medicine and mathematics in Venice, published there in 1724, 'Mathematical exercises'. Members of the Bernoulli family, like many scholars of those years, had a wide range of interests, not only because they were curious. The fact that the number of university departments has been limited and the vacancy is usually opened only after the death of Professor. Therefore, young people tended to be versed in different disciplines, and knowledge of several languages allows you to search the place and in other countries.

Getting a job in a small University of Basel Daniel Bernoulli failed, and he and his brother Nicholas accepted the invitation to the newly established St. Petersburg Academy of Sciences. In this regard, their father wrote: '... It is better to suffer some of the harsh climate in the country, where the welcome music, than to die of hunger in the country with a temperate climate, in which the muses hurt and despise '.

In October 1725 the brothers arrived in St. Petersburg. Daniel became an academician in physiology, and Nick - Mechanics. Unfortunately, a few months after his arrival he died.

Daniel spent a lot of observations of the motion, digestion, eyesight, breathing, formation rates in animals, published an article about this, but later worked mainly mechanics and mathematics, and astronomy. Here he is generally prepared his major work 'Hydrodynamics', which laid the foundation of this science, published the book in Strasbourg in 1738.

Petersburg Academy of Sciences owes her stay in this remarkable scientist. In her journals, he has published over 50 articles. But the Daniel Bernoulli wrote: 'I am glad to announce that the main part of this work (' Hydrodynamics'. - Authors.) Must guide, support schemes and the St. Petersburg Academy of Sciences. Reason for writing this book has a resolution of the Academy, in which the first professors gathered for its establishment, committed, and then definitely encouraged to write the arguments of some useful and, if possible, a new theme ... This my work has one goal - to benefit the Academy, all the efforts which aim to ensure that promote growth and social benefits of good science '. The brothers spoke with gratitude of the St. Petersburg Academy of Sciences, providing them with opportunities for work and learning.

In 1733 Daniel Bernoulli returned to Basel, where he became professor of anatomy and botany, and in 1750-m - Experimental Physics. He was a naturalist in the broad sense. Mathematics is regarded as a necessary tool for solving various problems of physics and mechanics. Was convinced nyutoniantsem, although Newton's perceived critical. In my work on tides, . The award-winning Paris Academy of Sciences in 1740, . Bernoulli wrote: 'If I had some success, . I must carry him to the honor of the scientist philosopher, . it was he who gave us the opportunity to talk reasonably about these issues',
. One, and together with his father and brother Daniel has won 10 prizes of the Paris Academy of Sciences.

According to contemporaries, Daniel Bernoulli was kind, witty, generous and donated large sums of the University of Basel, founded a hotel for poor students. He was a foreign member of many academies, including Paris, Berlin, St. Petersburg (from 1733), Royal Society of London, Turin, Bologna Institute. The St. Petersburg Academy for his initiative to invite Euler, and when he went blind, Daniel Bernoulli has sent his assistants to his talented and diligent pupils NI Fuss.

Princess E.R. Dashkova invited to the St. Petersburg Academy of Sciences and Jacob II nephew Daniel. He was first an associate (assistant professor), then academic, has published several articles, but in the spring of 1789, basking in the Neva River, was drowned.