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Pierre-Simon Laplace

 
Pierre Simon Laplace

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Pierre-Simon Laplace



 
 
Pierre-Simon, marquis de Laplace (23 April 1749 – 5 March 1827) was a French
France

France , officially the French Republic , is a country whose Metropolitan France is located in Western Europe and that also comprises various Overseas departments and territories of France....
 mathematician
Mathematician

A mathematician is a person whose primary area of study and/or research is the field of mathematics....
 and astronomer
Astronomer

An astronomer is a scientist who studies Celestial body such as planets, stars, and Galaxy.Historically, astronomy was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using physical laws....
 whose work was pivotal to the development of mathematical astronomy
Astronomy

Astronomy is the science of Astronomical object and Phenomenon that originate outside the Earth's atmosphere . It is concerned with the evolution, physics, chemistry, meteorology, and motion of celestial objects, as well as the physical cosmology....
 and statistics
Statistics

Statistics is a Mathematics pertaining to the collection, analysis, interpretation or explanation, and presentation of data. It also provides tools for prediction and forecasting based on data....
. He summarized and extended the work of his predecessors in his five volume Mécanique Céleste (Celestial Mechanics) (1799-1825). This seminal work translated the geometric
Geometry

Geometry arose as the field of knowledge dealing with spatial relationships. Geometry was one of the two fields of pre-modern mathematics, the other being the study of numbers....
 study of classical mechanics
Classical mechanics

Classical mechanics is used for describing the motion of macroscopic objects, from projectiles to parts of machinery, as well as astronomical objects, such as spacecraft, planets, stars, and galaxies....
 to one based on calculus
Calculus

Calculus is a branch of mathematics that includes the study of limit , derivatives, integrals, and infinite series, and constitutes a major part of modern university education....
, opening up a broader range of problems. In statistics, the so-called Bayesian interpretation
Bayesian probability

Bayesian probability interprets the concept of probability as 'a measure of a state of knowledge' , and not as a frequentist . Broadly speaking, there are two views on Bayesian probability that interpret the 'state of knowledge' concept in different ways....
 of probability was mainly developed by Laplace.

He formulated Laplace's equation
Laplace's equation

In mathematics, Laplace's equation is a partial differential equation named after Pierre-Simon Laplace who first studied its properties. The solutions of Laplace's equation are important in many fields of science, notably the fields of electromagnetism, astronomy, and fluid dynamics, because they describe the behavior of electric, gravitation...
, and invented the Laplace transform
Laplace transform

In mathematics, the Laplace transform is one of the best known and most widely used integral transforms. It is commonly used to produce an easily solvable algebraic equation from an ordinary differential equation....
 which appears in many branches of mathematical physics
Mathematical physics

Mathematical physics is the scientific discipline concerned with the interface of mathematics and physics. There is no real consensus about what does or does not constitute mathematical physics....
, a field that he took a leading role in forming.






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Quotations


Nature laughs at the difficulties of integration.

Quoted in I. Gordon and S. Sorkin, The Armchair Science Reader, New York, 1959. ----

Sire, je n'avais pas besoin de cette hypothèse-là.

Translation: "I did not need to make such an assumption."

La dernière chose que nous attendions de vous, Général, est une leçon de géométrie !.

Translation: "The last thing we expect of you, General, is a lesson in geometry!", Laplace to Napoléon, after the latter had reported on some new elementary geometry results ----

Il est facile de voir que...

Translation: "It is therefore obvious that...", Frequently used in the Traité de mécanique céleste when he had proved something and mislaid the proof, or found it clumsy. Notorious as a signal for something true, but hard to prove.





Encyclopedia


Pierre-Simon, marquis de Laplace (23 April 1749 – 5 March 1827) was a French
France

France , officially the French Republic , is a country whose Metropolitan France is located in Western Europe and that also comprises various Overseas departments and territories of France....
 mathematician
Mathematician

A mathematician is a person whose primary area of study and/or research is the field of mathematics....
 and astronomer
Astronomer

An astronomer is a scientist who studies Celestial body such as planets, stars, and Galaxy.Historically, astronomy was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using physical laws....
 whose work was pivotal to the development of mathematical astronomy
Astronomy

Astronomy is the science of Astronomical object and Phenomenon that originate outside the Earth's atmosphere . It is concerned with the evolution, physics, chemistry, meteorology, and motion of celestial objects, as well as the physical cosmology....
 and statistics
Statistics

Statistics is a Mathematics pertaining to the collection, analysis, interpretation or explanation, and presentation of data. It also provides tools for prediction and forecasting based on data....
. He summarized and extended the work of his predecessors in his five volume Mécanique Céleste (Celestial Mechanics) (1799-1825). This seminal work translated the geometric
Geometry

Geometry arose as the field of knowledge dealing with spatial relationships. Geometry was one of the two fields of pre-modern mathematics, the other being the study of numbers....
 study of classical mechanics
Classical mechanics

Classical mechanics is used for describing the motion of macroscopic objects, from projectiles to parts of machinery, as well as astronomical objects, such as spacecraft, planets, stars, and galaxies....
 to one based on calculus
Calculus

Calculus is a branch of mathematics that includes the study of limit , derivatives, integrals, and infinite series, and constitutes a major part of modern university education....
, opening up a broader range of problems. In statistics, the so-called Bayesian interpretation
Bayesian probability

Bayesian probability interprets the concept of probability as 'a measure of a state of knowledge' , and not as a frequentist . Broadly speaking, there are two views on Bayesian probability that interpret the 'state of knowledge' concept in different ways....
 of probability was mainly developed by Laplace.

He formulated Laplace's equation
Laplace's equation

In mathematics, Laplace's equation is a partial differential equation named after Pierre-Simon Laplace who first studied its properties. The solutions of Laplace's equation are important in many fields of science, notably the fields of electromagnetism, astronomy, and fluid dynamics, because they describe the behavior of electric, gravitation...
, and invented the Laplace transform
Laplace transform

In mathematics, the Laplace transform is one of the best known and most widely used integral transforms. It is commonly used to produce an easily solvable algebraic equation from an ordinary differential equation....
 which appears in many branches of mathematical physics
Mathematical physics

Mathematical physics is the scientific discipline concerned with the interface of mathematics and physics. There is no real consensus about what does or does not constitute mathematical physics....
, a field that he took a leading role in forming. The Laplacian differential operator
Laplace operator

In mathematics and physics, the Laplace operator or Laplacian, denoted by   or   and named after Pierre-Simon de Laplace, is a differential operator, specifically an important case of an elliptic operator, with many applications....
, widely used in applied mathematics
Mathematics

Mathematics is the study of quantity, structure, space, change, and related topics of pattern and form. Mathematicians seek out patterns whether found in numbers, space, natural science, computers, imaginary abstractions, or elsewhere....
, is also named after him.

He restated and developed the nebular hypothesis of the origin of the solar system and was one of the first scientists to postulate the existence of black hole
Black hole

In general relativity, a black hole is a region of space in which the gravitational field is so powerful that nothing, including electromagnetic radiation , can escape its pull after having fallen past its event horizon....
s and the notion of gravitational collapse
Gravitational collapse

Gravitational collapse in astronomy is the inward fall of a massive body under the influence of the force of gravity. It occurs when all other forces fail to supply a sufficiently high pressure to counterbalance gravity and keep the massive body in hydrostatic equilibrium....
.

He is remembered as one of the greatest scientists of all time, sometimes referred to as a French Newton
Isaac Newton

Sir Isaac Newton, Fellow of the Royal Society was an English people physicist, mathematician, Astronomy, Natural philosophy, Alchemy, and Theology and one of the the 100 in human history....
 or Newton of France, with a phenomenal natural mathematical faculty superior to any of his contemporaries.

He became a count
Count

A count is a nobleman in European countries; The word count comes from French language comte, itself from Latin comes?in its Accusative case comitem?meaning "companion", and later "companion of the emperor, delegate of the emperor"....
 of the First French Empire
First French Empire

The Empire of the French , also known as the Greater French Empire or First French Empire, but more commonly known as the Napoleonic Empire, was the empire of Napoleon I of France in France....
 in 1806 and was named a marquis
Marquis

Marquis is a French title of nobility. The English equivalent is Marquess, while in German, it is Markgraf.It may also refer to:Persons:...
 in 1817, after the Bourbon Restoration
Bourbon Restoration

Following the ousting of Napoleon I of France in 1814, the Allies restored the House of Bourbon to the France throne. The ensuing period is called the Restoration, following French usage, and is characterized by a sharp conservative reaction and the re-establishment of the Roman Catholic Church as a power in French politics....
.

Early life

Many details of the life of Laplace were lost when the family château
Château

A ch?teau is a manor house or residence of the lord of the manor or a country house of nobility or gentry, with or without fortifications, originally - and still most frequently - in French language-speaking regions....
 burned in 1925. Laplace was born in Beaumont-en-Auge
Beaumont-en-Auge

Beaumont-en-Auge is a Communes of France in the Calvados Departments of France in the Basse-Normandie r?gions of France in northwestern France. The city hosts one of the last kaleidoscope manufacturers in France....
, Normandy
Normandy

Normandy is a geographical region corresponding to the former Duchy of Normandy. It is situated along the coast of France south of the English Channel between Brittany and Picardy and comprises territory in northern France and the Channel Islands....
 in 1749. According to W. W. Rouse Ball
W. W. Rouse Ball

Walter William Rouse Ball was a United Kingdom mathematician, lawyer and a Fellow#Oxford, Cambridge, and Trinity of Trinity College, Cambridge from 1878 to 1905....
 (A Short Account of the History of Mathematics, 4th edition, 1908), he was the son of a small cottager or perhaps a farm-labourer, and owed his education to the interest excited in some wealthy neighbours by his abilities and engaging presence. Very little is known of his early years. It would seem from a pupil he became an usher in the school at Beaumont; but, having procured a letter of introduction to d'Alembert, he went to Paris to push his fortune. However, Karl Pearson
Karl Pearson

Karl Pearson Fellow of the Royal Society established the disciplineof mathematical statistics.In 1911 he founded the world's first university statistics department at University College London....
 is scathing about the inaccuracies in Rouse Ball's account and states,
Indeed Caen
Caen

Caen is a commune in France in northwestern France. It is the prefecture of the Calvados Departments of France and the capital of the Basse-Normandie r?gion in France....
 was probably in Laplace's day the most intellectually active of all the towns of Normandy. It was here that Laplace was educated and was provisionally a professor. It was here he wrote his first paper published in the Mélanges of the Royal Society of Turin, Tome iv. 1766-1769, at least two years before he went at 22 or 23 to Paris in 1771. Thus before he was 20 he was in touch with Lagrange
Joseph Louis Lagrange

Joseph-Louis Lagrange, born Giuseppe Lodovico Lagrangia was an Italy mathematician and astronomer, who lived most of his life in Prussia and France, making significant contributions to all fields of mathematical analysis, to number theory, and to classical mechanics and celestial mechanics....
 in Turin
Turín

Tur?n is a municipality in the Ahuachap?n Department Departments of El Salvador of El Salvador....
. He did not go to Paris a raw self-taught country lad with only a peasant background! In 1765 at the age of sixteen Laplace left the "School of the Duke of Orleans" in Beaumont and went to the University of Caen, where he appears to have studied for five years. The 'Ecole militaire' of Beaumont did not replace the old school until 1776.


His parents were from comfortable families. His father was Pierre Laplace, and his mother was Marie-Anne Sochon. The Laplace family were involved in agriculture until at least 1750, but Pierre Laplace senior was also a cider
Cider

Cider is an alcoholic beverage usually made from the fermentation juice of apples, although pears are also used.While any variety of apple may be used, certain cultivars are preferred in some regions, and these may be known as cider apples....
 merchant and syndic of the town of Beaumont.

Pierre Simon Laplace attended a school in the village run at a Benedictine
Benedictine

Benedictine refers to the spirituality and consecrated life in accordance with the Rule of St Benedict, written by Benedict of Nursia in the sixth century for the cenobitic communities he founded in central Italy....
 priory
Priory

A priory is a house of men or women under religious vows headed by a prior or prioress.Priories may be houses of mendicant friars or religious sisters , or monastery of monks or nuns ....
, his father intending that he would be ordained
Ordination

In general religious use, ordination is the process by which individuals are Consecration, that is, set apart as clergy to perform various religious rites and ceremonies....
 in the Roman Catholic Church
Roman Catholic Church

The Roman Catholic Church, officially known as the Catholic Church is the world's largest Christianity Ecclesia , representing over half of all Christians and one-sixth of the world population....
, and at sixteen he was sent to further his father's intention at the University of Caen, reading theology
Theology

Theology is the study of the existence or attributes of a deity or gods, or more generally the study of religion or spirituality. It is sometimes contrasted with religious studies: theology is understood as the study of religion from an internal perspective , and religious studies as the study of religion from an external perspective....
.

According to his great-great-grandson, d'Alembert received him rather poorly, and to get rid of him gave him a thick mathematics book, saying to come back when he had read it. When Laplace came back a few days later, d'Alembert was even less friendly and didn't hide his opinion that it was impossible that Laplace could have read and understood the book. But upon questioning him, he realized that it was true, and from that time he took Laplace under his care.

Another version is that Laplace solved overnight a problem that d'Alembert set him for submission the following week, then solved a harder problem the following night. D'Alembert was impressed and recommended him for a teaching place in the École Militaire
École Militaire

The ?cole Militaire is a vast complex of buildings housing various military teaching facilities located in Paris, France, southeast of the Champ de Mars....
.

With a secure income and undemanding teaching, Laplace now threw himself into original research
Original research

Original research is research that is not exclusively based on a summary, review or synthesis of earlier publications on the subject of research....
 and, in the next seventeen years, 1771-1787, he produced much of his original work in astronomy.

Laplace further impressed the Marquis de Condorcet
Marquis de Condorcet

Marie Jean Antoine Nicolas de Caritat, marquis de Condorcet was a France philosopher, mathematician, and early political science who devised the concept of a Condorcet method....
, and even in 1771 Laplace felt that he was entitled to membership in the French Academy of Sciences
French Academy of Sciences

The French Academy of Sciences is a learned society, founded in 1666 by Louis XIV of France at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French people Scientific method....
. However, in that year, admission went to Alexandre-Théophile Vandermonde
Alexandre-Théophile Vandermonde

Alexandre-Th?ophile Vandermonde was a France musician and chemist who worked with Bezout and Lavoisier; his name is now principally associated with determinant theory in mathematics....
 and in 1772 to Jacques Antoine Joseph Cousin. Laplace was disgruntled, and at the beginning of 1773, d'Alembert wrote to Lagrange
Lagrange

Lagrange may refer to:* Ch?teau Lagrange, the wine from Bordeaux, France* Joseph Louis Lagrange, mathematician and mathematical physicist* L?o Lagrange, French minister...
 in Berlin
Berlin

Berlin is the Capital of Germany city and one of sixteen States of Germany of Germany. With a population of 3.4 million within its city limits, Berlin is the country's largest city....
 to ask if a position could be found for Laplace there. However, Condorcet became permanent secretary of the Académie in February and Laplace was elected associate member on 31 March, at age 24.

He married Marie-Charlotte de Courty de Romanges in his late thirties and the couple had a daughter, Sophie, and a son, Charles-Émile (b. 1789).

Analysis, probability and astronomical stability

Laplace's early published work in 1771 started with differential equations and finite differences but he was already starting to think about the mathematical and philosophical concepts of probability
Probability

Probability, or wikt:chance, is a way of expressing knowledge or belief that an Event will occur or has occurred. In mathematics the concept has been given an exact meaning in probability theory, that is used extensively in such areas of study as mathematics, statistics, finance, gambling, science, and philosophy to draw conclusions about t...
 and statistics
Statistics

Statistics is a Mathematics pertaining to the collection, analysis, interpretation or explanation, and presentation of data. It also provides tools for prediction and forecasting based on data....
. However, before his election to the Académie in 1773, he had already drafted two papers that would establish his reputation. The first, Mémoire sur la probabilité des causes par les événements was ultimately published in 1774 while the second paper, published in 1776, further elaborated his statistical thinking and also began his systematic work on celestial mechanics
Celestial mechanics

Celestial mechanics is the branch of astronomy that deals with the motion s of celestial objects. The field applies principles of physics, historically classical mechanics, to astronomical objects such as stars and planets to produce ephemeris data....
 and the stability of the solar system
Solar System

The Solar System consists of the Sun and those Astronomical object bound to it by gravity: the eight planets and five dwarf planets, their 173 known Natural satellite, and billions of Small Solar System body....
. The two disciplines would always be interlinked in his mind. "Laplace took probability as an instrument for repairing defects in knowledge." Laplace's work on probability and statistics is discussed below with his mature work on the Analytic theory of probabilities.

Stability of the solar system

Sir Isaac Newton
Isaac Newton

Sir Isaac Newton, Fellow of the Royal Society was an English people physicist, mathematician, Astronomy, Natural philosophy, Alchemy, and Theology and one of the the 100 in human history....
 had published his Philosophiae Naturalis Principia Mathematica
Philosophiae Naturalis Principia Mathematica

The Philosophi? Naturalis Principia Mathematica is a three-volume work by Isaac Newton published on 5 July 1687. It contains the statement of Newton's laws of motion forming the foundation of classical mechanics, as well as his Newton's law of universal gravitation and a derivation of Kepler's laws of planetary motion for the motion of...
 in 1687 in which he gave a derivation of Kepler's laws, which describe the motion of the planet
Planet

A planet , as 2006 definition of planet by the International Astronomical Union , is a celestial body orbiting a star or Stellar evolution#Stellar remnants that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared the neighbourhood of planetesimals....
s, from his laws of motion
Newton's laws of motion

Newton's laws of motion are three physical laws that form the basis for classical mechanics, Direct relationship the forces acting on a Physical body to the motion of the body....
 and his law of universal gravitation
Newton's law of universal gravitation

Isaac Newton's law of universal gravitation is an empirical physical law describing the gravitational attraction between bodies with mass. It is a part of classical mechanics and was first formulated in Newton's work Philosophiae Naturalis Principia Mathematica, first published on July 5 1687....
. However, though Newton had privately developed the methods of calculus
Calculus

Calculus is a branch of mathematics that includes the study of limit , derivatives, integrals, and infinite series, and constitutes a major part of modern university education....
, all his published work used cumbersome geometric
Geometry

Geometry arose as the field of knowledge dealing with spatial relationships. Geometry was one of the two fields of pre-modern mathematics, the other being the study of numbers....
 reasoning, unsuitable to account for the more subtle higher-order effects of interactions between the planets. Newton himself had doubted the possibility of a mathematical solution to the whole, even concluding that periodic divine intervention
Miracle

File:Folio 171r - The Raising of Lazarus.jpgA miracle is a sensibly perceptible interruption of the laws of nature, such that can only be explained by divine intervention, and is sometimes associated with a miracle-worker....
 was necessary to guarantee the stability
Stability

Stability may refer to:...
 of the solar system. Dispensing with the hypothesis of divine intervention would be a major activity of Laplace's scientific life. It is now generally regarded that Laplace's methods on their own, though critical to the development of the theory, are not sufficiently precise
Accuracy and precision

In the fields of science, engineering, industry and statistics, accuracy is the degree of closeness of a Measure d or calculated quantity to its actual Value ....
 to demonstrate the stability of the Solar System
Stability of the Solar System

The stability of the Solar System is a subject of much inquiry in astronomy.The Solar System is chaos theory, though by most predictions it is stable in that none of the planets will collide with each other or be ejected from the system in the next few billion years, and the Earth's orbit will be relatively stable....
, and indeed, the Solar System is now understood to be chaotic
Chaos

Chaos typically refers to unpredictability, and is the antithesis of cosmos.The word did not mean "disorder" in classical-period ancient Greece....
, although in practice fairly stable.

One particular problem from observational astronomy
Observational astronomy

Observational astronomy is a division of the astronomy science that is concerned with getting data, in contrast with theoretical astrophysics which is mainly concerned with finding out the measurable implications of physical model s....
 was the apparent instability whereby Jupiter
Jupiter

Jupiter is the fifth planet from the Sun and the Solar system by size planet within the Solar System. It is two and a half times as massive as all of the other planets in our Solar System combined....
's orbit appeared to be shrinking while that of Saturn
Saturn

Saturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Saturn, along with Jupiter, Uranus and Neptune, is classified as a gas giant....
 was expanding. The problem had been tackled by Leonhard Euler
Leonhard Euler

Leonhard Paul Euler was a pioneering Swiss mathematician and physicist who spent most of his life in Russia and Germany.Euler made important discoveries in fields as diverse as calculus and graph theory....
 in 1748 and Joseph Louis Lagrange
Joseph Louis Lagrange

Joseph-Louis Lagrange, born Giuseppe Lodovico Lagrangia was an Italy mathematician and astronomer, who lived most of his life in Prussia and France, making significant contributions to all fields of mathematical analysis, to number theory, and to classical mechanics and celestial mechanics....
 in 1763 but without success. In 1776, Laplace published a memoir in which he first explored the possible influences of a purported luminiferous ether or of a law of gravitation that did not act instantaneously. He ultimately returned to an intellectual investment in Newtonian gravity. Euler and Lagrange had made a practical approximation by ignoring small terms in the equations of motion. Laplace noted that though the terms themselves were small, when integrated
Integral

Integration is an important concept in mathematics, specifically in the field of calculus and, more broadly, mathematical analysis. Given a function ƒ of a Real number variable x and an interval [ab] of the real line, the integral...
 over time
Time

Time is a component of the measurement used to sequence events, to compare the durations of events and the intervals between them, and to quantify the motions of objects....
 they could become important. Laplace carried his analysis into the higher-order terms, up to and including the cubic
Cubic

Cubic may refer to:...
. Using this more exact analysis, Laplace concluded that any two planets and the sun must be in mutual equilibrium and thereby launched his work on the stability of the solar system. Gerald James Whitrow
Gerald James Whitrow

Gerald James Whitrow was a British mathematician, physical cosmology and science historian.After completing school at Christ's Hospital, he obtained a scholarship at Christ Church, Oxford in 1930, earning his first degree in 1933, the MA in 1937, and the PhD in 1939....
 described the achievement as "the most important advance in physical astronomy since Newton".

Laplace had a wide knowledge of all sciences and dominated all discussions in the Académie. Laplace seems to have regarded analysis merely as a means of attacking physical problems, though the ability with which he invented the necessary analysis is almost phenomenal. As long as his results were true he took but little trouble to explain the steps by which he arrived at them; he never studied elegance or symmetry
Symmetry

Symmetry generally conveys two primary meanings. The first is an imprecise sense of harmonious or aesthetically-pleasing proportionality and balance; such that it reflects beauty or perfection....
 in his processes, and it was sufficient for him if he could by any means solve the particular question he was discussing.

On the figure of the Earth

During the years 1784-1787 he published some memoirs of exceptional power. Prominent among these is one read in 1783, reprinted as Part II of Théorie du Mouvement et de la figure elliptique des planètes in 1784, and in the third volume of the Méchanique céleste. In this work, Laplace completely determined the attraction of a spheroid
Spheroid

A spheroid is a quadric surface obtained by rotating an ellipse about one of its principal axes; in other words, an ellipsoid with two equal semi-diameters....
 on a particle outside it. This is memorable for the introduction into analysis of spherical harmonics
Spherical harmonics

In mathematics, the spherical harmonics are the angular portion of an orthogonal set of solutions to Laplace's equation represented in a system of spherical coordinates....
 or Laplace's coefficients, and also for the development of the use of the potential, a name first used by George Green
George Green

George Green was a United Kingdom mathematician and physicist, who wrote An Essay on the Application of Mathematical Analysis to the Theories of Electricity and Magnetism ....
 in 1828.

Spherical harmonics

Rotating Spherical Harmonics
In 1783, in a paper sent to the Académie, Adrien-Marie Legendre
Adrien-Marie Legendre

Adrien-Marie Legendre was a France mathematician. He made important contributions to statistics, number theory, abstract algebra and mathematical analysis....
 had introduced what are now known as associated Legendre functions. If two points in a plane
Plane (mathematics)

In mathematics, a plane is a curvature surface. Planes can arise as subspaces of some higher dimensional space, as with the walls of a room, or they may enjoy an independent existence in their own right, as in the setting of Euclidean geometry....
 have polar co-ordinates (r, ?) and (r ', ?'), where r ' = r, then, by elementary manipulation, the reciprocal of the distance between the points, d, can be written as:

This expression can be expanded in powers
Power series

In mathematics, a power series is an infinite series of the formwhere an represents the coefficient of the nth term, c is a constant, and x varies around c ....
 of r/r ' using Newton's generalized binomial theorem
Binomial theorem

In mathematics, the binomial theorem is an important formula giving the expansion of exponentiation of sums. Its simplest version states that...
 to give:

The sequence
Sequence

In mathematics, a sequence is an ordered list of objects . Like a Set , it contains Element , and the number of terms is called the length of the sequence....
 of functions P0k(cos?) is the set of so-called "associated Legendre functions" and their usefulness arises from the fact that every function
Function (mathematics)

The mathematical concept of a function expresses dependence between two quantities, one of which is known and the other which is produced. A function associates a single output to each input element drawn from a fixed Set , such as the real numbers , although different inputs may have the same output....
 of the points on a circle
Circle

A circle is a simple shape of Euclidean geometry consisting of those point in a plane which are the same distance from a given point called the center....
 can be expanded as a series
Series (mathematics)

In mathematics, given an infinite set sequence of numbers , a series is informally the result of adding all those terms together: . These can be written more compactly using the summation symbol ?....
 of them.

Laplace, with scant regard for credit to Legendre, made the non-trivial extension of the result to three dimensions
Three-dimensional space

Three-dimensional space is a geometric model of the physical universe in which we live. The three dimensions are commonly called length, width, and depth , although any three mutually perpendicular directions can serve as the three dimensions....
 to yield a more general set of functions, the spherical harmonics
Spherical harmonics

In mathematics, the spherical harmonics are the angular portion of an orthogonal set of solutions to Laplace's equation represented in a system of spherical coordinates....
 or Laplace coefficients. The latter term is not now in common use. Every function of the points on a sphere
Sphere

A sphere is a symmetrical geometrical object. In non-mathematical usage, the term is used to refer either to a round ball or to its two-dimensional surface....
 can be expanded as a series of them.

Potential theory

This paper is also remarkable for the development of the idea of the scalar potential
Scalar potential

A scalar potential is a fundamental concept in vector analysis and physics . Given a vector field F, its scalar potential V is a scalar field whose negative gradient is F,...
. The gravitational force acting on a body is, in modern language, a vector, having magnitude and direction. A potential function is a scalar
Scalar

A scalar is a variable that only has magnitude , e.g. a speed of 40 km/h. Compare it with vector, a quantity comprising both magnitude and Direction , e.g....
 function that defines how the vectors will behave. A scalar function is computationally and conceptually easier to deal with than a vector function.

Alexis Clairault
Alexis Clairault

Alexis Claude de Clairault was a France mathematician and intellectual....
 had first suggested the idea in 1743 while working on a similar problem though he was using Newtonian-type geometric reasoning. Laplace described Clairault's work as being "in the class of the most beautiful mathematical productions". However, Rouse Ball alleges that the idea "was appropriated from Joseph Louis Lagrange
Joseph Louis Lagrange

Joseph-Louis Lagrange, born Giuseppe Lodovico Lagrangia was an Italy mathematician and astronomer, who lived most of his life in Prussia and France, making significant contributions to all fields of mathematical analysis, to number theory, and to classical mechanics and celestial mechanics....
, who had used it in his memoirs of 1773, 1777 and 1780".

Laplace applied the language of calculus to the potential function and shows that it always satisfies the differential equation
Differential equation

A differential equation is a mathematics equation for an unknown function of one or several variable that relates the values of the function itself and its derivatives of various orders....


His subsequent work on gravitational attraction was based on this result. The quantity has been termed the concentration of and its value at any point indicates the "excess" of the value of there over its mean value in the neighbourhood of the point. Laplace's equation
Laplace's equation

In mathematics, Laplace's equation is a partial differential equation named after Pierre-Simon Laplace who first studied its properties. The solutions of Laplace's equation are important in many fields of science, notably the fields of electromagnetism, astronomy, and fluid dynamics, because they describe the behavior of electric, gravitation...
, a special case of Poisson's equation
Poisson's equation

In mathematics, Poisson's equation is a partial differential equation with broad utility in electrostatics, mechanical engineering and theoretical physics....
, appears ubiquitously in mathematical physics. The concept of a potential occurs in fluid dynamics
Fluid dynamics

In physics, fluid dynamics is the sub-discipline of fluid mechanics dealing with fluid flow — the natural science of fluids in motion....
, electromagnetism
Electromagnetism

Electromagnetism is the physics of the electromagnetic field, a field which exerts a force on Elementary particles with the property of electric charge and which is reciprocally affected by the presence and motion of such particles....
 and other areas. Rouse Ball speculated that it might be seen as "the outward sign" of one the "prior forms" in Kant's theory of perception
Immanuel Kant

Immanuel Kant was an 18th-century German Philosophy from the Kingdom of Prussia city of K?nigsberg . He is regarded as one of the most influential thinkers of modern Europe and of the late Age of Enlightenment....
.

The spherical harmonics turn out to be critical to practical solutions of Laplace's equation. Laplace's equation in spherical coordinates, such as are used for mapping the sky
Sky

The sky is the part of the atmosphere or of outer space visible from the surface of any astronomical object. It is difficult to define precisely for several reasons....
, can be simplified, using the method of separation of variables
Separation of variables

In mathematics, separation of variables is any of several methods for solving ordinary and partial differential equations, in which algebra allows one to rewrite an equation so that each of two variables occurs on a different side of the equation....
 into a radial part, depending solely on distance from the centre point, and an angular or spherical part. The solution to the spherical part of the equation can be expressed as a series of Laplace's spherical harmonics, simplifying practical computation.

Planetary inequalities

This memoir was followed by another on planetary inequalities, which was presented in three sections in 1784, 1785, and 1786. This deals mainly with the explanation of the "great inequality" of Jupiter and Saturn. Laplace showed by general considerations that the mutual action of two planets could never largely affect the eccentricities and inclinations of their orbits; and that the peculiarities of the Jovian system were due to the near approach to commensurability of the mean motions of Jupiter and Saturn: further developments of these theorems on planetary motion were given in his two memoirs of 1788 and 1789. It was on these data that Delambre computed his astronomical tables.

It had been observed that since ancient times the Moon
Moon

The Moon is Earth's only natural satellite and the List of natural satellites by diameter satellite in the Solar System. The average centre-to-centre distance from the Earth to the Moon is km, about thirty times the diameter of the Earth....
's overall orbital speed was changing over time. In 1693, Edmond Halley
Edmond Halley

Edmond Halley Royal Society was an English astronomer, geophysicist, mathematician, meteorologist, and physicist.Biography and career ...
 had shown that the rate of the drift in position was increasing, an effect known as the secular acceleration of the Moon. Laplace gave an explanation in 1787 in terms of changes in the eccentricity of the Earth's orbit
Equation of time

The equation of time is the difference over the course of a year between time as read from a sundial and time as read from a clock, measured in an ideal situation ....
. However, in 1853, John Couch Adams
John Couch Adams

John Couch Adams , was a British mathematician and astronomer. Adams was born in Laneast, Cornwall and died in Cambridge, England. The Cornish language name Couch is pronounced "cooch"....
 went on to show that Laplace had only considered the radial force on the moon and not the tangential, and hence had failed to explain more than half of the drift. The other half was subsequently shown to be due to tidal acceleration
Tidal acceleration

Tidal acceleration is an effect of the tidal forces between an orbiting natural satellite , and the planet that it orbits. The "acceleration" is usually negative, as it causes a gradual slowing and recession of a satellite in a prograde orbit away from the primary, and a corresponding slowdown of the primary's rotation....
. However, Laplace was still able to use his result to complete his "proof" of the stability of the whole solar system
Stability of the Solar System

The stability of the Solar System is a subject of much inquiry in astronomy.The Solar System is chaos theory, though by most predictions it is stable in that none of the planets will collide with each other or be ejected from the system in the next few billion years, and the Earth's orbit will be relatively stable....
 on the assumption that it consists of a collection of rigid bodies
Rigid body

In physics, a rigid body is an idealization of a solid Physical body of finite size in which deformation is neglected. In other words, the distance between any two given Point s of a rigid body remains constant in time regardless of external forces exerted on it....
 moving in a vacuum
Vacuum

A vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure. The word comes from the Latin term for "empty," but in reality, no volume of space can ever be perfectly empty....
.

All the memoirs above alluded to were presented to the Académie des sciences, and they are printed in the Mémoires présentés par divers savants.

Celestial mechanics

Laplace now set himself the task to write a work which should "offer a complete solution of the great mechanical problem presented by the solar system
Solar System

The Solar System consists of the Sun and those Astronomical object bound to it by gravity: the eight planets and five dwarf planets, their 173 known Natural satellite, and billions of Small Solar System body....
, and bring theory to coincide so closely with observation that empirical equations should no longer find a place in astronomical tables." The result is embodied in the Exposition du système du monde and the Mécanique céleste.

The former was published in 1796, and gives a general explanation of the phenomena, but omits all details. It contains a summary of the history of astronomy. This summary procured for its author the honour of admission to the forty of the French Academy and is commonly esteemed one of the masterpieces of French literature, though it is not altogether reliable for the later periods of which it treats.

Laplace developed the nebular hypothesis of the formation of the solar system, first suggested by Emanuel Swedenborg
Emanuel Swedenborg

was a Sweden scientist, philosopher, Christian mystic, and theologian. Swedenborg had a prolific career as an inventor and scientist. At the age of fifty-six he entered into a spiritual phase in which he experienced dreams and visions....
 and expanded by Immanuel Kant
Immanuel Kant

Immanuel Kant was an 18th-century German Philosophy from the Kingdom of Prussia city of K?nigsberg . He is regarded as one of the most influential thinkers of modern Europe and of the late Age of Enlightenment....
, a hypothesis that continues to dominate accounts of the origin of planetary systems. According to Laplace's description of the hypothesis, the solar system had evolved from a globular mass of incandescent
Incandescence

Incandescence is the emission of light from a hot body due to its temperature. The term derives from the verb incandesce, to grow white....
 gas
Gas

In physics, a gas is a state of matter, consisting of a collection of particles without a definite shape or volume that are in more or less random motion....
 rotating around an axis through its centre of mass. As it cooled, this mass contracted, and successive rings broke off from its outer edge. These rings in their turn cooled, and finally condensed into the planet
Planet

A planet , as 2006 definition of planet by the International Astronomical Union , is a celestial body orbiting a star or Stellar evolution#Stellar remnants that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared the neighbourhood of planetesimals....
s, while the sun
Sun

The Sun , a G V star, is the star at the center of the Solar System. The Earth and other matter orbit the Sun, which by itself accounts for about 98.6% of the Solar System's mass....
 represented the central core which was still left. On this view, Laplace predicted that the more distant planets would be older than those nearer the sun.

As mentioned, the idea of the nebular hypothesis had been outlined by Immanuel Kant
Immanuel Kant

Immanuel Kant was an 18th-century German Philosophy from the Kingdom of Prussia city of K?nigsberg . He is regarded as one of the most influential thinkers of modern Europe and of the late Age of Enlightenment....
 in 1755, and he had also suggested "meteoric aggregations" and tidal friction as causes affecting the formation of the solar system. Laplace was probably aware of this, but, like many writers of his time, he generally did not reference the work of others.

Laplace's analytical discussion of the solar system is given in his Méchanique céleste published in five volumes. The first two volumes, published in 1799, contain methods for calculating the motions of the planets, determining their figures, and resolving tidal problems. The third and fourth volumes, published in 1802 and 1805, contain applications of these methods, and several astronomical tables. The fifth volume, published in 1825, is mainly historical, but it gives as appendices the results of Laplace's latest researches. Laplace's own investigations embodied in it are so numerous and valuable that it is regrettable to have to add that many results are appropriated from other writers with scanty or no acknowledgement, and the conclusions - which have been described as the organized result of a century of patient toil - are frequently mentioned as if they were due to Laplace.

Jean-Baptiste Biot
Jean-Baptiste Biot

Jean-Baptiste Biot was a France physicist, astronomer and mathematician who established the reality of meteorite....
, who assisted Laplace in revising it for the press, says that Laplace himself was frequently unable to recover the details in the chain of reasoning, and, if satisfied that the conclusions were correct, he was content to insert the constantly recurring formula, "Il est aisé à voir que..." ("It is easy to see that..."). The Mécanique céleste is not only the translation of Newton's Principia into the language of the differential calculus
Differential calculus

Differential calculus, a field in mathematics, is the study of how function s change when their inputs change. The primary object of study in differential calculus is the derivative....
, but it completes parts of which Newton had been unable to fill in the details. The work was carried forward in a more finely tuned form in Félix Tisserand
Félix Tisserand

Fran?ois F?lix Tisserand was a France astronomer.Tisserand was born at Nuits-Saint-Georges, C?te d'Or. In 1863 he entered the Ecole Normale Superieure, and on leaving he went for a month as professor at the lycee at Metz....
's Traité de mécanique céleste (1889-1896), but Laplace's treatise will always remain a standard authority.

Arcueil

In 1806, Laplace bought a house in Arcueil
Arcueil

Arcueil is a commune in France in the Val-de-Marne Departments of France located in what can be considered as the southern suburbs of Paris, France....
, then a village and not yet absorbed into the Paris conurbation
Conurbation

A conurbation is an urban area or agglomeration comprising a number of cities, large towns and larger urban areas that, through population growth and physical expansion, have merged to form one continuous urban and industrially developed area....
. Claude Louis Berthollet
Claude Louis Berthollet

Claude Louis Berthollet was a Duchy of Savoyard-French chemist who became vice president of the French Senate in 1804....
 was a near neighbour and the pair formed the nucleus of an informal scientific circle, latterly known as the Society of Arcueil. Because of Laplace and Berthollet's closeness to Napoleon, they effectively controlled advancement in the scientific establishment and admission to the more prestigious offices. The Society built up a complex pyramid of patronage
Patronage

Patronage is the support, encouragement, privilege and often financial aid that an organization or individual bestows to another. In the history of art, arts patronage refers to the support that kings or popes have provided to musicians, painters, and sculptors....
.

Laplace and Napoleon

An account of a famous interaction between Laplace and Napoleon is provided by Rouse Ball:

"Laplace went in state to Napoleon to accept a copy of his work, and the following account of the interview is well authenticated, and so characteristic of all the parties concerned that I quote it in full. Someone had told Napoleon that the book contained no mention of the name of God; Napoleon, who was fond of putting embarrassing questions, received it with the remark, 'M. Laplace, they tell me you have written this large book on the system of the universe, and have never even mentioned its Creator.' Laplace, who, though the most supple of politicians, was as stiff as a martyr on every point of his philosophy, drew himself up and answered bluntly, 'Je n'avais pas besoin de cette hypothèse-là.' ['I had no need of that hypothesis.'] Napoleon, greatly amused, told this reply to Lagrange
Lagrange

Lagrange may refer to* Ch?teau Lagrange, the wine from Bordeaux, France* Joseph Louis Lagrange, mathematician and mathematical physicist* L?o Lagrange, French minister...
, who exclaimed, 'Ah! c'est une belle hypothèse; ça explique beaucoup de choses.' ['Ah, it is a fine hypothesis; it explains so many things.']"


Black holes

Laplace also came close to propounding the concept of the black hole
Black hole

In general relativity, a black hole is a region of space in which the gravitational field is so powerful that nothing, including electromagnetic radiation , can escape its pull after having fallen past its event horizon....
. He pointed out that there could be massive stars whose gravity is so great that not even light could escape from their surface (see escape velocity
Escape velocity

In physics, escape velocity is the speed where the kinetic energy of an object is equal to the magnitude of its gravitational potential energy, as calculated by the equation,...
). Laplace also speculated that some of the nebulae revealed by telescopes may not be part of the Milky Way
Milky Way

The Milky Way, sometimes called simply the Galaxy, is the galaxy in which the Solar System is located. It is a barred spiral galaxy that is part of the Local Group of galaxies....
 and might actually be galaxies themselves. Thus, he anticipated the major discovery of Edwin Hubble
Edwin Hubble

Edwin Powell Hubble was an United States Astronomy. He profoundly changed astronomers' understanding of the nature of the universe by demonstrating the existence of other galaxies besides the Milky Way....
, some 100 years before it happened.

Analytic theory of probabilities

In 1812, Laplace issued his Théorie analytique des probabilités in which he laid down many fundamental results in statistics
Statistics

Statistics is a Mathematics pertaining to the collection, analysis, interpretation or explanation, and presentation of data. It also provides tools for prediction and forecasting based on data....
. In 1819, he published a popular account of his work on probability. This book bears the same relation to the Théorie des probabilités that the Système du monde does to the Méchanique céleste.

Probability-generating function

The method of estimating the ratio of the number of favourable cases, compared to the whole number of possible cases, had been previously indicated by Laplace in a paper written in 1779. It consists of treating the successive values of any function
Function (mathematics)

The mathematical concept of a function expresses dependence between two quantities, one of which is known and the other which is produced. A function associates a single output to each input element drawn from a fixed Set , such as the real numbers , although different inputs may have the same output....
 as the coefficients in the expansion of another function, with reference to a different variable. The latter is therefore called the probability-generating function
Probability-generating function

In probability theory, the probability-generating function of a discrete random variable is a power series representation of the probability mass function of the random variable....
 of the former. Laplace then shows how, by means of interpolation
Interpolation

In the mathematics subfield of numerical analysis, interpolation is a method of constructing new data points within the range of a discrete set of known data points....
, these coefficients may be determined from the generating function. Next he attacks the converse problem, and from the coefficients he finds the generating function; this is effected by the solution of a finite difference equation.

Least squares

This treatise includes an exposition of the method of least squares, a remarkable testimony to Laplace's command over the processes of analysis. The method of least squares for the combination of numerous observations had been given empirically by Carl Friedrich Gauss
Carl Friedrich Gauss

Johann Carl Friedrich Gauss. was a Germans mathematician and scientist who contributed significantly to many fields, including number theory, statistics, mathematical analysis, Differential geometry and topology, geodesy, electrostatics, astronomy and optics....
 (around 1794) and Legendre (in 1805), but the fourth chapter of this work contains a formal proof of it, on which the whole of the theory of errors has been since based. This was affected only by a most intricate analysis specially invented for the purpose, but the form in which it is presented is so meagre and unsatisfactory that, in spite of the uniform accuracy of the results, it was at one time questioned whether Laplace had actually gone through the difficult work he so briefly and often incorrectly indicates.

Inductive probability


While he conducted much research in physics
Physics

Physics is the natural science which examines basic concepts such as energy, force, and spacetime and all that derives from these, such as mass, charge, matter and its Motion ....
, another major theme of his life's endeavours was probability theory
Probability theory

Probability theory is the branch of mathematics concerned with analysis of Statistical randomness phenomena. The central objects of probability theory are random variables, stochastic processes, and event s: mathematical abstractions of determinism events or measured quantities that may either be single occurrences or evolve over time in an a...
. In his Essai philosophique sur les probabilités (1814), Laplace set out a mathematical system of inductive reasoning based on probability
Probability

Probability, or wikt:chance, is a way of expressing knowledge or belief that an Event will occur or has occurred. In mathematics the concept has been given an exact meaning in probability theory, that is used extensively in such areas of study as mathematics, statistics, finance, gambling, science, and philosophy to draw conclusions about t...
, which we would today recognise as Bayesian
Bayesian probability

Bayesian probability interprets the concept of probability as 'a measure of a state of knowledge' , and not as a frequentist . Broadly speaking, there are two views on Bayesian probability that interpret the 'state of knowledge' concept in different ways....
. He begins the text with a series of principles of probability, the first six being:

1) Probability is the ratio of the "favored events" to the total possible events.

2) The probability of all possible events are equal, or we must find another unit of probabilistic measurement which will commensurate the measurement of the probability of all possible events.

3) For independent events, the probability of the occurence of all is the probability of each multiplied together.

4) For events not independent, the probability of event B following event A (or event A causing B) is the probability of A multiplied by the probability that A and B both occur.

5) The probability that A will occur, given B has occurred, is the probability of A divided by the probability of B.

6) Three correlaries are given for the sixth principle, which amount to Bayesian probability. Where event exhausts the list of possible causes for event B, . Then .

One well-known formula arising from his system is the rule of succession
Rule of succession

In probability theory, the rule of succession is a formula introduced in the 18th century by Pierre-Simon Laplace in the course of treating the sunrise problem....
, given as principle seven. Suppose that some trial has only two possible outcomes, labeled "success" and "failure". Under the assumption that little or nothing is known a priori about the relative plausibilities of the outcomes, Laplace derived a formula for the probability
Probability

Probability, or wikt:chance, is a way of expressing knowledge or belief that an Event will occur or has occurred. In mathematics the concept has been given an exact meaning in probability theory, that is used extensively in such areas of study as mathematics, statistics, finance, gambling, science, and philosophy to draw conclusions about t...
 that the next trial will be a success.

where s is the number of previously observed successes and n is the total number of observed trials. It is still used as an estimator for the probability of an event if we know the event space, but only have a small number of samples.

The rule of succession has been subject to much criticism, partly due to the example which Laplace chose to illustrate it. He calculated that the probability that the sun will rise tomorrow, given that it has never failed to in the past, was

where d is the number of times the sun has risen in the past. This result has been derided as absurd, and some authors have concluded that all applications of the Rule of Succession are absurd by extension. However, Laplace was fully aware of the absurdity of the result; immediately following the example, he wrote, "But this number [i.e., the probability that the sun will rise tomorrow] is far greater for him who, seeing in the totality of phenomena the principle regulating the days and seasons, realizes that nothing at the present moment can arrest the course of it."

Criticism remains powerful, though. The concepts rely upon the prescription to assign equal probability when there is insufficient information about the probability of the existence of the causes. For finite causes, the principle implies no known absurdities. However, consider the famous case where you are told that a machine randomly produces cubes with edge-lengths between one meter and three. The probability of the machine then producing cubes with edges of length one to two meters will seem a priori to be one-half.

If we merely re-conceptualize the probability, though, we will see that the machine produces cubes of volume between one cubic meter and 27 cubic meters. And when we investigate the probability of the machine producing cubes with edge length between one and two meters, we ask the probability of the machine producing cubes of volume between one and eight cubic meters. And yet the likelihood of a machine to produce cubes of volume between one and eight cubic meters, which randomly produces cubes between one and 27 cubic meters, the resultant likelihood should be less than half, since eight is less than half of 27.

Laplace's demon

Laplace strongly believed in causal determinism, which is expressed in the following quote from the introduction to the Essai:

This intellect is often referred to as Laplace's demon
Laplace's demon

In the history of science, Laplace's demon is a hypothetical "demon" envisioned in 1814 by Pierre-Simon Laplace such that if it knew the precise location and momentum of every atom in the universe then it could use Newton's laws to reveal the entire course of cosmic events, past and future....
 (in the same vein as Maxwell's demon
Maxwell's demon

Maxwell's demon was an 1867 thought experiment by the Scotland physicist James Clerk Maxwell, meant to raise questions about the possibility of violating the second law of thermodynamics....
). Note that the description of the hypothetical intellect described above by Laplace as a demon
Demon

In religion, folklore, and mythology a demon is a supernatural being that is generally described as a malevolent spirit. In Christian terms demons are generally understood as fallen angels, formerly of God....
 does not come from Laplace, but from later biographers: Laplace saw himself as a scientist who hoped that humanity would progress in a better scientific understanding of the world, which, if and when eventually completed, would still need a tremendous calculating power to compute it all in a single instant.

Laplace transforms

As early as 1744, Euler, followed by Lagrange
Lagrange

Lagrange may refer to:* Ch?teau Lagrange, the wine from Bordeaux, France* Joseph Louis Lagrange, mathematician and mathematical physicist* L?o Lagrange, French minister...
, had started looking for solutions of differential equation
Differential equation

A differential equation is a mathematics equation for an unknown function of one or several variable that relates the values of the function itself and its derivatives of various orders....
s in the form:

In 1785, Laplace took the key forward step in using integrals of this form in order to transform a whole difference equation, rather than simply as a form for the solution, and found that the transformed equation was easier to solve than the original.

Other discoveries and accomplishments


Mathematics

Amongst the other discoveries of Laplace in pure and applicable mathematics are:
  • Discussion, contemporaneously with Alexandre-Théophile Vandermonde
    Alexandre-Théophile Vandermonde

    Alexandre-Th?ophile Vandermonde was a France musician and chemist who worked with Bezout and Lavoisier; his name is now principally associated with determinant theory in mathematics....
    , of the general theory of determinant
    Determinant

    In algebra, a determinant is a function depending on n that associates a scalar , det, to an n?n square matrix A. The fundamental geometric meaning of a determinant is a scale factor for measure when A is regarded as a linear transformation....
    s, (1772);
  • Proof that every equation of an even degree must have at least one real
    Real number

    In mathematics, the real numbers may be described informally in several different ways. The real numbers include both rational numbers, such as 42 and −23/129, and irrational numbers, such as pi and the square root of two; or, a real number can be given by an infinite decimal representation, such as 2.4871773339...., where the digits co...
     quadratic
    Quadratic

    In mathematics, the term quadratic describes something that pertains to Square , to the operation of squaring, to terms of the second degree of a polynomial, or equations or formulas that involve such terms....
     factor;
  • Solution of the linear partial differential equation of the second order;
  • He was the first to consider the difficult problems involved in equations of mixed differences, and to prove that the solution of an equation in finite differences of the first degree and the second order might be always obtained in the form of a continued fraction
    Continued fraction

    In mathematics, a continued fraction is an expression such aswhere a0 is an integer and all the other numbers ai are positive integers....
    ; and
  • In his theory of probabilities:
    • Evaluation of several common definite integrals; and
    • General proof of the Lagrange reversion theorem
      Lagrange reversion theorem

      In mathematics, the Lagrange reversion theorem gives Series or formal power series expansions of certain implicitly defined functions; indeed, of compositions with such functions....
      .


Surface tension

Laplace built upon the qualitative work of Thomas Young
Thomas Young (scientist)

Thomas Young was an England polymath who made notable contributions to the fields of Visual perception, light, solid mechanics, energy, physiology, language, harmony and Egyptology....
 to develop the theory of capillary action
Capillary action

Capillary action, capillarity, capillary motion, or wicking refers to two phenomena:# The movement of liquids in thin tubes...
 and the Young-Laplace equation.

Speed of sound

Laplace in 1816 was the first to point out that the speed of sound
Speed of sound

Sound is a vibration that travels through an elasticity medium as a wave. The speed of sound describes how much distance such a wave travels in a certain amount of time....
 in air
AIR

Air is the part of Earth's atmosphere that humans breath and as such Air .Air may also refer to:...
 depends on the heat capacity ratio
Heat capacity ratio

The heat capacity ratio or adiabatic index or ratio of specific heats, is the ratio of the heat capacity at constant pressure to heat capacity at constant volume ....
. Newton's original theory gave too low a value, because it does not take account of the adiabatic
Adiabatic process

In thermodynamics, an adiabatic process or an isocaloric process is a thermodynamic process in which no heat is transferred to or from the working fluid....
 compression of the air which results in a local rise in temperature
Temperature

In physics, temperature is a physical property of a Physical system that underlies the common notions of hot and cold; something that feels hotter generally has the greater temperature....
 and pressure
Pressure

Pressure is the force per unit area applied to an object in a direction surface normal to the surface. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure....
. Laplace's investigations in practical physics were confined to those carried on by him jointly with Lavoisier in the years 1782 to 1784 on the specific heat of various bodies.

Political ambitions

According to W. W. Rouse Ball
W. W. Rouse Ball

Walter William Rouse Ball was a United Kingdom mathematician, lawyer and a Fellow#Oxford, Cambridge, and Trinity of Trinity College, Cambridge from 1878 to 1905....
, as Napoleon's power increased Laplace begged him to give him the post of Minister of the Interior
Minister of the Interior (France)

The Minister of the Interior in France is one of the most important governmental French government ministers, responsible for the following:* The general interior security of the country, with respect to criminal acts or natural catastrophes...
. However this is disputed by Pearson
Karl Pearson

Karl Pearson Fellow of the Royal Society established the disciplineof mathematical statistics.In 1911 he founded the world's first university statistics department at University College London....
. Napoleon, who desired the support of men of science, did make him Minister of the Interior in November 1799, but a little less than six weeks saw the close of Laplace's political career. Napoleon later (in his Mémoires de Sainte Hélène) wrote of his dismissal as follows:

Although Laplace was removed from office, it was desirable to retain his allegiance. He was accordingly raised to the senate, and to the third volume of the Mécanique céleste he prefixed a note that of all the truths therein contained the most precious to the author was the declaration he thus made of his devotion towards the peacemaker of Europe. In copies sold after the Bourbon Restoration
Bourbon Restoration

Following the ousting of Napoleon I of France in 1814, the Allies restored the House of Bourbon to the France throne. The ensuing period is called the Restoration, following French usage, and is characterized by a sharp conservative reaction and the re-establishment of the Roman Catholic Church as a power in French politics....
 this was struck out. (Pearson points out that the censor would not have allowed it anyway.) In 1814 it was evident that the empire was falling; Laplace hastened to tender his services to the Bourbons, and in 1817 during the Restoration
Bourbon Restoration

Following the ousting of Napoleon I of France in 1814, the Allies restored the House of Bourbon to the France throne. The ensuing period is called the Restoration, following French usage, and is characterized by a sharp conservative reaction and the re-establishment of the Roman Catholic Church as a power in French politics....
 he was rewarded with the title of marquis
Marquis

Marquis is a French title of nobility. The English equivalent is Marquess, while in German, it is Markgraf.It may also refer to:Persons:...
.

According to Rouse Ball, the contempt that his more honest colleagues felt for his conduct in the matter may be read in the pages of Paul Louis Courier
Paul Louis Courier

Paul Louis Courier , France Hellenist and political writer, was born in Paris.Brought up on his father's estate of M?r? in Touraine, he conceived a bitter aversion for the nobility, which seemed to strengthen with time....
. His knowledge was useful on the numerous scientific commissions on which he served, and probably accounts for the manner in which his political insincerity was overlooked.

He died in Paris in 1827. His brain was removed by his physician, François Magendie
François Magendie

Fran?ois Magendie was a France physiologist, considered a pioneer in experimental physiology. He is known for describing the foramen of Magendie....
, and kept for many years, eventually being displayed in an roving anatomical museum in Britain. It was reportedly smaller than the average brain.

Honours

  • Asteroid
    Asteroid

    Asteroids, sometimes called minor planets or planetoids, are small Solar System bodies in orbit around the Sun, smaller than planets but larger than meteoroids....
     4628 Laplace
    4628 Laplace

    4628 Laplace is a Main-belt Asteroid discovered on September 07, 1986 by E. W. Elst at Rozhen....
     is named for him.
  • He is one of only seventy-two people to have their name engraved on the Eiffel Tower.
  • The European Space Agency
    European Space Agency

    The European Space Agency , established in 1975, is an intergovernmentalism organisation dedicated to the Space exploration, currently with 18 member states....
    's working-title for the international Europa Jupiter System Mission
    Europa Jupiter System Mission

    The Europa Jupiter System Mission is a proposed joint ESA/NASA unmanned space mission for the in-depth exploration of Jupiter's moons with a focus on Europa , Ganymede and Jupiter's magnetosphere; its working name at ESA is Laplace....
     is "Laplace".


Quotes

  • What we know is not much. What we do not know is immense. (attributed)
  • I had no need of that hypothesis. ("Je n'avais pas besoin de cette hypothèse-là", as a reply to Napoleon
    Napoleon I of France

    Napoleon Bonaparte later known as Emperor Napoleon I, was a military and political leader of France whose actions shaped European politics in the early 19th century....
    , who had asked why he hadn't mentioned God in his book on astronomy
    Astronomy

    Astronomy is the science of Astronomical object and Phenomenon that originate outside the Earth's atmosphere . It is concerned with the evolution, physics, chemistry, meteorology, and motion of celestial objects, as well as the physical cosmology....
    .)
  • "It is therefore obvious that ..." (frequently used in the Celestial Mechanics when he had proved something and mislaid the proof, or found it clumsy. Notorious as a signal for something true, but hard to prove.)
  • The weight of evidence for an extraordinary claim must be proportioned to its strangeness. (known as the Principle of Laplace)


See also



Bibliography


By Laplace

  • , 14 vol. (1878–1912), Paris: Gauthier-Villars (in French) (PDF copy from Gallica)
  • Théorie du movement et de la figure elliptique des planètes (1784) Paris (not in Œuvres complètes)

English translations
  • Bowditch, N.
    Nathaniel Bowditch

    Nathaniel Bowditch was an early American mathematician remembered for his work on ocean navigation. He is often credited as the founder of modern maritime navigation; his book American Practical Navigator, first published in 1802, is still carried onboard every commissioned U.S....
     (trans.) (1829-1839) Mécanique céleste, 4 vols, Boston
    • New edition by Reprint Services ISBN 078122022X
  • — [1829-1839] (1966-1969) Celestial Mechanics, 5 vols, including the original French
  • Pound, J. (trans.) (1809) The System of the World, 2 vols, London: Richard Phillips
  • _
  • _
  • — [1809] (2007) The System of the World, vol.1, Kessinger, ISBN 1432653679
  • Toplis, J. (trans.) (1814) Nottingham: H. Barnett


  • , translated from the French 6th ed. (1840)


About Laplace and his work

  • (in French)**David, F. N. (1965) "Some notes on Laplace", in Neyman, J.
    Jerzy Neyman

    Jerzy Neyman , born Jerzy Splawa-Neyman, was a Polish-American mathematician and statistician.He was born into a Poles family in Bendery, Bessarabia in Imperial Russia, the fourth of four children of Czeslaw Splawa-Neyman and Kazimiera Lutoslawska....
     & LeCam, L. M. (eds) Bernoulli, Bayes and Laplace, Berlin, pp30-44***, delivered 15 June 1829, published in 1831. (in French)*— (1997) Pierre Simon Laplace 1749-1827: A Life in Exact Science, Princeton: Princeton University Press, ISBN 0-691-01185-0
  • Grattan-Guiness, I.
    Ivor Grattan-Guinness

    Ivor Grattan-Guinness is a historian of mathematics and logic.He gained his Bachelor degree as a Mathematics Scholar at Wadham College, Oxford, got an M.Sc in Mathematical Logic and the Philosophy of Science at the London School of Economics in 1966....
    , 2005, "'Exposition du système du monde' and 'Traité de méchanique céleste'" in his Landmark Writings in Western Mathematics. Elsevier: 242-57.**— (2005) Pierre Simon Laplace 1749-1827: A Determined Scientist, Cambridge, MA: Harvard University Press, ISBN 0-674-01892-3*Rouse Ball, W. W.
    W. W. Rouse Ball

    Walter William Rouse Ball was a United Kingdom mathematician, lawyer and a Fellow#Oxford, Cambridge, and Trinity of Trinity College, Cambridge from 1878 to 1905....
     [1908] (2003) "", in A Short Account of the History of Mathematics, 4th ed., Dover, ISBN 0486206300*
  • Whitrow, G. J.
    Gerald James Whitrow

    Gerald James Whitrow was a British mathematician, physical cosmology and science historian.After completing school at Christ's Hospital, he obtained a scholarship at Christ Church, Oxford in 1930, earning his first degree in 1933, the MA in 1937, and the PhD in 1939....
     (2001) "Laplace, Pierre-Simon, marquis de", Encyclopaedia Britannica, Deluxe CDROM edition** (available from Google Books)


External links

  • "" in the MacTutor History of Mathematics archive
    MacTutor History of Mathematics archive

    The MacTutor History of Mathematics archive is an award-winning website maintained by John J. O'Connor and Edmund F. Robertson and hosted by the University of St Andrews in Scotland....
    .*