Adrien-Marie Legendre (1752-1833)
Adrien-Marie Legendre (1752-1833) was a person.
References
2015
- (Wikipedia, 2015) ⇒ http://en.wikipedia.org/wiki/Adrien-Marie_Legendre Retrieved:2015-11-9.
- Adrien-Marie Legendre (18 September 1752 – 10 January 1833) was a French mathematician. Legendre made numerous contributions to mathematics. Well-known and important concepts such as the Legendre polynomials and Legendre transformation are named after him.
2015
- (Wikipedia, 2015) ⇒ http://en.wikipedia.org/wiki/Adrien-Marie_Legendre#Scientific_activity Retrieved:2015-11-9.
- Most of his work was brought to perfection by others: his work on roots of polynomials inspired Galois theory; Abel's work on elliptic functions was built on Legendre's; some of Gauss' work in statistics and number theory completed that of Legendre. He developed the least squares method and firstly communicated it to his contemporaries before Gauss, which has broad application in linear regression, signal processing, statistics, and curve fitting; this was published in 1806 as an appendix to his book on the paths of comets. Today, the term "least squares method" is used as a direct translation from the French "méthode des moindres carrés".
Around 1811 he named the gamma function and introduced the symbol Γ normalizing it to Γ(n+1) = n!.
In 1830 he gave a proof of Fermat's last theorem for exponent n = 5, which was also proven by Lejeune Dirichlet in 1828.
In number theory, he conjectured the quadratic reciprocity law, subsequently proved by Gauss; in connection to this, the Legendre symbol is named after him. He also did pioneering work on the distribution of primes, and on the application of analysis to number theory. His 1798 conjecture of the Prime number theorem was rigorously proved by Hadamard and de la Vallée-Poussin in 1896.
Legendre did an impressive amount of work on elliptic functions, including the classification of elliptic integrals, but it took Abel's stroke of genius to study the inverses of Jacobi's functions and solve the problem completely.
He is known for the Legendre transformation, which is used to go from the Lagrangian to the Hamiltonian formulation of classical mechanics. In thermodynamics it is also used to obtain the enthalpy and the Helmholtz and Gibbs (free) energies from the internal energy. He is also the namegiver of the Legendre polynomials, solutions to Legendre's differential equation, which occur frequently in physics and engineering applications, e.g. electrostatics.
Legendre is best known as the author of Éléments de géométrie, which was published in 1794 and was the leading elementary text on the topic for around 100 years. This text greatly rearranged and simplified many of the propositions from Euclid's Elements to create a more effective textbook.
- Most of his work was brought to perfection by others: his work on roots of polynomials inspired Galois theory; Abel's work on elliptic functions was built on Legendre's; some of Gauss' work in statistics and number theory completed that of Legendre. He developed the least squares method and firstly communicated it to his contemporaries before Gauss, which has broad application in linear regression, signal processing, statistics, and curve fitting; this was published in 1806 as an appendix to his book on the paths of comets. Today, the term "least squares method" is used as a direct translation from the French "méthode des moindres carrés".
1806
- (Legendre, 1805) ⇒ Adrien-Marie Legendre. (1805). “Nouvelle formula pour réduire en distances vraies les distances apparentes de la Lune au Soleil ou à une étoile."