Marc-Antoine Parseval

Marc-Antoine Parseval des Chênes (April 27, 1755 – August 16, 1836) was a French mathematician, most famous for what is now known as Parseval's theorem, which presaged the unitarity of the Fourier transform.

He was born in Rosieres-aux-Salines, in France, into an aristocratic French family, and married Ursule Guerillot in 1795, but divorced her soon thereafter. A monarchist opposed to the French revolution, Parseval fled the country after being imprisoned in 1792 by Napoleon for publishing poetry critical of the government.

Later, he was nominated to the Paris Academy of Sciences five times, from 1796 to 1828, but was never elected. His only mathematical publications were, apparently, five papers, published in 1806 as Mémoires présentés à l'Institute des Sciences, Lettres et Arts, par divers savans, es lus dans ses assemblées. Sciences mathématiques et physiques. (Savans étrangers.) This combined the following earlier monographs:

1. "Mémoire sur les résolution des équations aux différences partielles linéaires du second ordre," (May 5, 1798).
2. "Mémoire sur les séries et sur l'integration complète d'une équation aux différences partielles linéaires du second ordre, à coefficents constants," (April 5, 1799).
3. "Intégration générale et compléte des équations de la propagation du son, l'air étant considéré avec ses trois dimensions," (July 5, 1801).
4. "Intégration générale et complète de deux équations importantes dans la mécanique de fluides," (August 16, 1803).
5. "Méthode génerale pour sommer, par le moyen des intégrales définies, la suite donnée par le théoréme de M. Lagrange, au moyen de laquelle il trouve une valeur qui satisfait à une équation algébrique ou transcendente," (May 7, 1804).

It was in the second, 1799, memoir in which he stated, but did not prove (claiming it to be self-evident), the theorem that now bears his name. He further expanded upon it in his 1801 memoir, and used it to solve various differential equations. The theorem was first printed in 1800 as a part (p. 377) of Traité des différences et des séries by Lacroix.

References

• Parseval, MacTutor History of Mathematics archive.
• Hubert Kennedy, Eight Mathematical Biographies (Peremptory Publications: San Francisco, 2002).