Pierre-Simon Laplace was a prominent French mathematical physicist and astronomer of the 19th century, who made crucial contributions in the arena of planetary motion by applying Sir Isaac Newton’s theory of gravitation to the entire solar system. His work regarding the theory of probability and statistics is considered pioneering and has influenced a whole new generation of mathematicians.

### Early Life and Education:

Born on 23 March in 1749, Pierre-Simon Laplace entered Caen University when he was only 16 and he soon developed a strong interest in mathematics. When he was only 19, he moved to Paris, without finishing his degree, to work as a professor of mathematics at the École Militaire with the fellow mathematician Jean-le-Rond D’Alembert. Five years later, Laplace had already written 13 scientific papers regarding integral calculus, mechanics and physical astronomy, which gained him fame and acclaim all over France.

### Contributions and Achievements:

Pierre-Simon Laplace is highly regarded for his influential five-volume treatise “Traité de mécanique céleste” (Celestial mechanics; 1799-1825), which developed a strong mathematical understanding of the motion of the heavenly bodies, including several anomalies and inequalities that were noticed in their orbits. Laplace suggested that the nature of the universe is completely deterministic.

Laplace heavily contributed in the development of differential equations, difference equations, probability and statistics. His 1812 work “Théorie analytique des probabilités” (Analytic theory of probability) furthered the subjects of probability and statistics significantly.

Laplace was made a member of the Paris Academic des Sciences in 1773, where he assumed a senior position in 1785. He was given the duty of standardizing all European weights and measures.

His work on celestial mechanics is considered revolutionary. He established that the small perturbations observed in the orbital motion of the planets will always remain small, constant and self-correcting. He was the earliest astronomer to suggest the idea that the solar system originated from the contraction and cooling of a large rotating, and consequently flattened, nebula of incandescent gas. Laplace published his famous work on probability in 1812. He supplied his own definition of probability and applied it to justify the fundamental mathematical manipulations.

### Later Life and Death:

Laplace died in Paris, France, on March 5, 1827. He was 77 years old. It is impossible to overstate the influence Laplace had on the progress of the mathematical theory of mechanics. Various fundamental concepts, for instance the Laplace operator in potential theory and the Laplace transform in the study of differential equations, are named after him.