Pierre Alphonse Laurent (18 July 1813 – 2 September 1854) was a French mathematician, engineer, and Military Officer best known for discovering the
Laurent series
In mathematics, the Laurent series of a complex function f(z) is a representation of that function as a power series which includes terms of negative degree. It may be used to express complex functions in cases where a Taylor series expansio ...
, an expansion of a
function into an
infinite power series
In mathematics, a power series (in one variable) is an infinite series of the form
\sum_^\infty a_n \left(x - c\right)^n = a_0 + a_1 (x - c) + a_2 (x - c)^2 + \dots
where ''a_n'' represents the coefficient of the ''n''th term and ''c'' is a co ...
, generalizing the
Taylor series
In mathematics, the Taylor series or Taylor expansion of a function is an infinite sum of terms that are expressed in terms of the function's derivatives at a single point. For most common functions, the function and the sum of its Taylor ser ...
expansion.
Life
He was born in Paris, France. His father, Pierre Michel Laurent (1769 – 1841) was French, whereas his mother, Eleanor Cheshire (1778 – 1840) was English. Pierre Laurent entered the École Polytechnique in Paris in 1830 and graduated in 1832 as one of the best students in his year. Afterwards, he joined the engineering corps as a second lieutenant, before attending the École d'Application at
Metz
Metz ( , , , then ) is a city in northeast France located at the confluence of the Moselle (river), Moselle and the Seille (Moselle), Seille rivers. Metz is the Prefectures in France, prefecture of the Moselle (department), Moselle Departments ...
until he was sent to
Algeria
Algeria, officially the People's Democratic Republic of Algeria, is a country in the Maghreb region of North Africa. It is bordered to Algeria–Tunisia border, the northeast by Tunisia; to Algeria–Libya border, the east by Libya; to Alger ...
.
Laurent returned to France from Algeria around 1840 and spent six years directing operations for the enlargement of the port of
Le Havre
Le Havre is a major port city in the Seine-Maritime department in the Normandy (administrative region), Normandy region of northern France. It is situated on the right bank of the estuary of the Seine, river Seine on the English Channel, Channe ...
on the English Channel coast.
Rouen
Rouen (, ; or ) is a city on the River Seine, in northwestern France. It is in the prefecture of Regions of France, region of Normandy (administrative region), Normandy and the Departments of France, department of Seine-Maritime. Formerly one ...
had been the main French port up to the nineteenth century, but the hydraulic construction projects on which Laurent worked in Le Havre turned it into France's main seaport. It is clear that Laurent was a good engineer, putting his deep theoretical knowledge to good practical use.
Mathematics
It was while Laurent was working on the construction project at Le Havre that he began to write his first mathematical papers. He submitted a memoir for the Grand Prize of the
Académie des Sciences of 1842. His result was contained in a memoir submitted for the Grand Prize of the
Académie des Sciences in 1843, but his submission was after the due date, and the paper was not published and never considered for the prize. Laurent died at age 41 in Paris. His work was not published until after his death. Possibly the result was first discovered by
Karl Weierstrass
Karl Theodor Wilhelm Weierstrass (; ; 31 October 1815 – 19 February 1897) was a German mathematician often cited as the " father of modern analysis". Despite leaving university without a degree, he studied mathematics and trained as a school t ...
in an 1841 paper, but not published at the time.
[.]
See also
*
Laurent polynomial
References
External links
*
1813 births
1854 deaths
Scientists from Paris
19th-century French mathematicians
French mathematical analysts
{{France-mathematician-stub