Laplace, Pierre Simon

1995/08/02 Azkune Mendia, Iñaki - Elhuyar Fundazioa | Kaltzada, Pili - Elhuyar Zientziaren Komunikazioa

• Biografiak

(1749-1827)

Astronomer, mathematician and French physicist was born in Beaumont in Auge in 1749. She was a humble family, but with the help of her neighbors she was able to go to school and train in mathematics. He immediately stood out and at the age of 18 moved to Paris. d'Albert requested the help of the mathematician, but this one refused. Laplace did not yield and sent d'Alembert an essay on mechanics. This high quality work was promoted by d'Alembert as the chair of mathematics. In addition, the sponsor of Laplace was able to appoint professor of Normal School and Polytechnic School.

Laplace took his first steps in the field of physics, mainly in the study of specific calors. In 1780 he claimed that the amount of heat necessary for the decomposition of a substance together with Lavoisier is equal to the amount of heat produced by its components when generating it. In other words, they enunciated the fundamental basis of current thermochemistry and contributed the first concepts of energy conservation.

Laplace was then in charge of astronomy. He claimed that in 1787 the acceleration of the Moon increased and that this had much to do with the orbit of the Earth and the rest of the planets. He began to analyze the duration of the average movements of the planets, as he considered that it depended on this balance of the Solar System. Thus, he affirmed that the forces that generate interaction between the orbits of the planets around the Sun guarantee the balance of the Solar System. All these theories were published in five books, Mécanique Céleste, published between 1799 and 1825, collecting the contributions of Newton, d'Alembert or Halley.

In 1796 he published a book entitled Exposition du système du monde. In it he collected the theory of the System of Planets, published in several journals. He claimed that the entire mechanism of the Universe could be expressed through mathematical functions and that all future events could be predicted.

Although he liked astronomy, Laplace never abandoned mathematics and did many studies on the calculation of probabilities. The most prominent were compiled in a large book entitled Théorie analytique des probabilités, published in 1795 and 1812. The book was printed twice when Laplace lived.

For many, Laplac's contributions are also due to his ability to adapt to the changes that occurred in France. He was assistant to Napoleon and in 1806 gave him the title of count. When Napoleon fell, he adapted perfectly to the new regime and Louis XVIII. the king appointed him marquis. Since 1785 he was a member of the Academy of Sciences and in 1817, a year after his approval at the French Academy, he was appointed director of the institution.

When he was about to turn 78, Count and Marquis Pierre Simon Laplace died in Paris.