Joseph-Louis Lagrange summary

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Below is the article summary. For the full article, see Joseph-Louis Lagrange, comte de l’Empire.

Joseph-Louis Lagrange, later count de L’Empire, (born Jan. 25, 1736, Turin, Sardinia-Piedmont—died April 10, 1813, Paris, France), Italian-born French mathematician who made important contributions to number theory and to classical and celestial mechanics. By age 25 he was recognized as one of the greatest living mathematicians because of his papers on wave propagation (see wave motion) and maxima and minima (see maximum; minimum) of curves. His prodigious output included his textbook Mécanique analytique (1788), the basis for all later work in this field. His remarkable discoveries included the Lagrangian, a differential operator characterizing a system’s physical state, and the Lagrangian points, points in space where a small body in the gravitational fields of two large ones remains relatively stable.

Moon Summary

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metric system Summary

Metric system, international decimal system of weights and measures, based on the metre for length and the kilogram for mass, that was adopted in France in 1795 and is now used officially in almost all countries. The French Revolution of 1789 provided an opportunity to pursue the frequently

number theory Summary

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celestial mechanics Summary

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