Many researchers believe that Joseph Lagrange is not a French, but an Italian mathematician. And they adhere to this opinion not without reason. After all, the future researcher was born in Turin, in 1736. During baptism, the boy was named Giuseppe Ludovico. His father held a high political post under the administration of Sardinia, and also belonged to the noble class. Mother came from a wealthy family of a doctor.
Family of the future mathematician
Therefore, at first, the family in which Joseph Louis Lagrange was born was quite wealthy. But the father of the family was inept, and yet very persistent businessman. Therefore, they soon stood on the brink of ruin. In the future, Lagrange expresses a very interesting opinion about this life circumstance that befell his family. He believes that if his family continued to live a rich and prosperous life, then perhaps Lagrange would never have a chance to connect his fate with mathematics.
The book that turned life upside down
The eleventh child of his parents was Joseph Louis Lagrange. His biography even in this respect can be called successful: after all, all his other brothers and sisters died in early childhood. Lagrange's father was disposed to ensure that his son was educated in the field of jurisprudence. Lagrange himself at first was not opposed. At first he studied at Turin College, where he was very interested in foreign languages and where the future mathematician first became acquainted with the works of Euclid and Archimedes.
However, that fatal moment comes when Lagrange first catches the eye of Galileo's work entitled “On the Advantages of the Analytical Method”. Joseph Louis Lagrange was incredibly interested in this book - perhaps it was she who turned his whole future destiny. Almost instantly for a young scientist, jurisprudence and foreign languages remained in the shadow of mathematical science.
According to some sources, Lagrange was doing mathematics on his own. According to others, he went to classes at the Turin School. Already at the age of 19 (and according to some sources - at 17), Joseph Louis Lagrange taught mathematics at the university. This was due to the fact that the best students of the country at that time had the opportunity to teach.
First work: in the footsteps of Leibniz and Bernoulli
So, from now on, mathematics has become the main field of Lagrange. In 1754, his first study was released. The scientist designed it in the form of a letter to the Italian scientist Fagnano dei Tosca. However, Lagrange makes a mistake here. Without a supervisor and preparing independently, he subsequently discovers: his research has already been carried out. The conclusions made by him belonged to Leibniz and Johann Bernoulli. Joseph Louis Lagrange even feared accusations of plagiarism. But his fears were completely in vain. And ahead of the mathematician, great achievements were expected.
Meet Euler
In the years 1755-1756, the young scientist sent several of his developments to the famous mathematician Euler, which he highly praised. And in 1759, Lagrange sent him another very important study. It was devoted to methods for solving isoperimetric problems that Euler had been struggling with for many years. An experienced scientist was very pleased with the discoveries of the young Lagrange. He even refused to publish some of his developments in this field until Joseph Louis Lagrange published his own work.
In 1759, thanks to a proposal by Euler, Lagrange took up the post of foreign member of the Berlin Academy of Sciences. Euler showed a little trick here: after all, he really wanted Lagrange to live as close to him as possible, and thus the young scientist could move to Berlin.
Work and overwork
Lagrange was not only engaged in research in mathematics, mechanics, and astronomy. He also created the scientific community, which later became the Royal Academy of Sciences of Turin. But at the price that Joseph Louis Lagrange developed a huge number of theories in exact fields and at that time became the greatest mathematician and astronomer in the world, there were bouts of depression.
The beginning to remind myself of constant overwork. Doctors in 1761 declared: they are not going to be responsible for the health of Lagrange unless he dies his research ardor and stabilizes the work schedule. The mathematician did not show willfulness and obeyed the recommendations of doctors. His health has stabilized. But depression did not leave him until the end of his life.
Astronomy Research
In 1762, an interesting competition was announced by the Paris Academy of Sciences. To participate in it was necessary to provide work on the movement of the moon. And here Lagrange manifests himself as an astronomer researcher. In 1763, he sends his work on the liberation of the moon for consideration by the commission. And the article itself arrives at the Academy shortly before the arrival of Lagrange himself. The fact is that mathematics had to travel to London, during which he became seriously ill and was forced to stop in Paris.
But here Lagrange also found great benefits: after all, in Paris, he managed to meet another great scientist - D'Alembert. In the French capital, Lagrange receives an award for his research on the libration of the moon. And another prize is awarded to the scientist - two years later he was awarded for research on two moons of Jupiter.
High post
In 1766, Lagrange returned to Berlin and received an offer to become president of the Academy of Sciences and head of its physics and mathematics department. Many Berlin scholars have very welcomed Lagrange into their society. He managed to establish strong friendships with mathematicians Lambert, Johann Bernoulli. But in this society there were also ill-wishers. One of them was Castiglion, who was three dozen years older than Lagrange. But after a while, their relationship improved. Lagrange married a cousin of Castiglion named Vittoria. However, their marriage was childless and unhappy. Often a sick wife died in 1783.
The main book of the scientist
In total, the scientist spent more than twenty years in Berlin. The most productive work is considered the "Analytical Mechanics" of Lagrange. This study was written at the time of his maturity. There are only a few great scientists whose heritage would have included such a fundamental work. "Analytical mechanics" is comparable to the "Beginnings" of Newton, as well as with the "Pendulum Clock" Huygens. It also formulated the famous “Lagrange Principle”, the more complete name of which is the “D'Alembert-Lagrange Principle”. It belongs to the field of general equations of dynamics.
Transfer to Paris. Sunset of life
In 1787, Lagrange moved to Paris. He was completely satisfied with the work in Berlin, but this had to be done for the reason that the position of foreigners after the death of Frederick II in the city was gradually deteriorating. A royal audience was held in honor of Lagrange in Paris, and the mathematician even got an apartment in the Louvre. But at the same time, he begins a serious bout of depression. In 1792, the scientist married a second time, and now the union was happy.
At the end of his life, the scientist has published many more works. The last work he planned to undertake was the revision of Analytical Mechanics. But the scientist failed to do this. On April 10, 1813, Joseph Louis Lagrange died. His quotes, especially one of the last, characterize his whole life: "I did my job ... I never hated anyone and did no harm to anyone." The death of the scientist, like life, was calm - he left with a sense of accomplishment.