Encyclopedia, Difference between revisions of "James Clerk Maxwell" - New World

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'''James Clerk Maxwell''' (13 June 1831 – 5 November 1879) was a [[Scotland|Scottish]] [[Mathematical physics|mathematician and theoretical physicist]]. His most significant achievement was formulating a set of equations — [[eponym]]ously named [[Maxwell's equations]] — that for the first time expressed the basic laws of [[electricity]] and [[magnetism]] in a unified fashion. He also developed the [[Maxwell-Boltzmann distribution|Maxwell distribution]], a statistical means to describe aspects of the [[kinetic theory|kinetic theory of gases]]. These two discoveries helped usher in the era of modern physics, laying the foundation for future work in such fields as [[Theory of relativity|special relativity]] and [[quantum mechanics]]. He is also known for creating the first true color photograph in 1861.
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'''James Clerk Maxwell''' (13 June 1831 – 5 November 1879) was a [[Scotland|Scottish]] [[Mathematical physics|mathematician and theoretical physicist]]. He developed a mathematical expression that described the actions of electricty and magnetism and their interrelationship, and from these predicted the existence of electromagnetic waves traveling at the speed of light. Maxwell was also the first to peer into the dimensions of the molecular world by calculating the average distance a gas molecule travels before it hits another molecule. Maxwell also produced the first color photograph.
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The majority of Maxwell's illustrious career took place at the [[University of Cambridge]], where his investigations often made use of his mathematical aptitude, drawing on elements of geometry and algebra. With these skills, Maxwell was able to demonstrate that [[electric force|electric]] and [[magnetic field]]s travel through space, in the form of [[waves]], and at the constant speed of light. Finally, in 1861 Maxwell wrote a four-part publication in the ''Philosophical Magazine'' called [http://www.vacuum-physics.com/Maxwell/maxwell_oplf.pdf On Physical Lines of Force] where he first proposed that [[light]] was in fact undulations in the same medium that is the cause of electric and magnetic phenomena.
 
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Maxwell is considered by many, especially those within the field of physics, to be the scientist of the nineteenth century most influential on twentieth century physics. His contributions to physics are considered by many to be of the same magnitude as those of [[Isaac Newton]] and [[Albert Einstein]].{{Fact|date=March 2007}} In 1931, on the centennial anniversary of Maxwell's birthday, Einstein described Maxwell's work as the "''most profound and the most fruitful that physics has experienced since the time of Newton.''"
 
  
 
== Biography ==
 
== Biography ==
 
===Early life and education===
 
===Early life and education===
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James Clerk Maxwell was born on June 13, 1831 in Edinburgh, Scotland, to John Clerk and Frances (née Cay) Maxwell. His birthplace, at 15 India Street, is now the location of the [[International Centre for Mathematical Sciences]]. It was at this time that physicist [[Michael Faraday]] was in the process of completing his work on [[magnetic induction]], a concept upon which Maxwell would later build.
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James Clerk Maxwell was born on June 13, 1831 in Edinburgh, Scotland, to John Clerk and Frances (née Cay) Maxwell. His birthplace, at 15 India Street, is now the location of the [[International Centre for Mathematical Sciences]].
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Maxwell grew up on his father's estate in the Scottish countryside. He was encouraged by his father to pursue his scientific and mathematical interests. Maxwell entered college at the age of 16 and eventually graduated with high honors in mathematics. All indications suggest that Maxwell had maintained an unquenchable curiosity from an early age.  By the age of three, everything that moved, shone, or made a noise drew the question: "what's the go o' that?".<ref>{{cite book|author=Mahon, Basil |title=The Man Who Changed Everything – the Life of James Clerk Maxwell|location=Hoboken, NJ | publisher=Wiley|year=2003|id=ISBN 0-470-86171-1}}</ref> In a letter to her sister Jane Cay in 1834, his mother describes this innate sense of inquisitiveness:
 
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<blockquote> He is a very happy man, and has improved much since the weather got moderate; he has great work with doors, locks, keys, etc., and 'show me how it doos' is never out of his mouth. He also investigates the hidden course of streams and bell-wires, the way the water gets from the pond through the wall...<ref>{{cite book
 
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  | last = Tolstoy
 
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  | first = Ivan
 
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  | title = James Clerk Maxwell: A Biography
 
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  | publisher = [[Cannongate]]
 
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  | location = Edinburgh
 
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  | date = 1981
 
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  | pages = 12
 
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  | id = ISBN 086241010X }}</ref></blockquote>
 
  
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Recognizing the potential of young Maxwell, his mother Frances took responsibility for his early education, which in Victorian times was largely the job of the women of the house. She became ill — probably with cancer — and died in 1839. His father, John Clerk Maxwell, undertook the education of his son, with the aid of his sister-in-law Jane Cay, both of whom played pivotal roles in the life of James. His formal education began, unsuccessfully, under the guidance of a hired tutor. Not much is known about the man James's father hired to instruct his son, except that he treated the younger Maxwell harshly. His educational philosophy was founded upon coercion, often physical. James never responded well to the tutor's instruction; he chided his student for being slow and wayward. After considerable searching, John Maxwell sent James to the [[Edinburgh Academy]]. His school nickname was ''"[[wiktionary:daft|Daft]]ie"'', earned when he arrived for his first day of school wearing home-made shoes.  
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Maxwell grew up on his father's estate in Dumfrieshire in the Scottish countryside. Maxwell's parents quickly recognized their son's inquisitive nature. His mother took responsibility for his early education, which in Victorian times was largely the job of the women of the house. She died in 1839, however, when Maxwell was only eight. His father then undertook the education of his son with the aid of his sister-in-law Jane Cay, both of whom played pivotal roles in Maxwell's life. His formal education began under the guidance of a hired tutor, but finding this arrangement less than satisfactory, John Maxwell sent his son to the [[Edinburgh Academy]].
  
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Maxwell was captivated by [[geometry]] at an early age, rediscovering the [[regular polyhedra]] before any formal instruction. Much of his talent went unnoticed however, and his academic work remained unremarkable until, in 1845 at the age of 13, he won the school's mathematical medal, and first prizes for English and for English verse. For his first piece of original work, at the age of 14, Maxwell wrote a paper describing mechanical means of drawing [[mathematical curves]] with a piece of [[twine]] and properties of [[ellipse]]s and curves with more than two [[Focus (geometry)|foci]]. This work, ''Oval Curves'', was published in an issue of the ''Royal Society of Edinburgh'', and although it shows the curiosity of Maxwell at a young age, it is important to note that the work itself was not mathematically profound. Unlike other great minds, such as [[Carl Friedrich Gauss|Gauss]], [[Blaise Pascal|Pascal]] or [[Wolfgang Amadeus Mozart|Mozart]], Maxwell was not a [[child prodigy]]. Rather, his genius would slowly mature.
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Maxwell was captivated by [[geometry]] at an early age. Much of his talent went unnoticed however, and his academic work remained unremarkable until, in 1845 at the age of 13, he won the school's mathematical medal, and first prizes for English and for English verse. His first piece of original work, at the age of 14 was a paper describing mechanical means of drawing [[mathematical curves]] with a piece of [[twine]], and properties of [[ellipse]]s and curves with more than two [[Focus (geometry)|foci]]. This work, ''Oval Curves'', was published in an issue of the ''Royal Society of Edinburgh'', and although it shows the curiosity of Maxwell at a young age, it is important to note that the work itself was not mathematically profound. Unlike other great minds, such as [[Carl Friedrich Gauss|Gauss]], [[Blaise Pascal|Pascal]] or [[Wolfgang Amadeus Mozart|Mozart]], Maxwell was not a [[child prodigy]]. Rather, his genius would slowly mature.
  
 
===Middle years===
 
===Middle years===
 
[[Image:YoungJamesClerkMaxwell.jpg|thumb|left|A young Maxwell at university.]]
 
[[Image:YoungJamesClerkMaxwell.jpg|thumb|left|A young Maxwell at university.]]
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Maxwell left the [[Edinburgh Academy|Academy]] and began attending class at the [[University of Edinburgh]]. Having the opportunity to attend Cambridge after his first term, Maxwell decided instead to complete the full three terms of his undergraduate studies at Edinburgh. The main reason for this was that Cambridge was too far from home, and he would only have the opportunity to see his father twice a year. Another reason was Maxwell's  concern for his future. He wanted to become a scientist, but jobs in science were rare at this time, and it would have been difficult to obtain a lecturing post at a university. Accordingly, Maxwell completed his studies at Edinburgh in [[natural philosophy]], [[moral philosophy]], and mental philosophy under [[Sir William Hamilton, 9th Baronet]]. In his eighteenth year he contributed two papers for the ''Transactions of the [[Royal Society of Edinburgh]]'' &mdash; one of which, ''On the Equilibrium of Elastic Solids'', laid the foundation for an important discovery of his later life: the temporary [[double refraction]] produced in [[viscosity|viscous]] [[liquid]]s by [[shear stress]].
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Maxwell left the [[Edinburgh Academy|Academy]] in 1847 and enrolled at the [[University of Edinburgh]]. He completed his studies at Edinburgh in [[natural philosophy]], [[moral philosophy]], and mental philosophy under [[Sir William Hamilton, 9th Baronet]]. In his eighteenth year he contributed a paper to ''Transactions of the [[Royal Society of Edinburgh]]'', ''On the Equilibrium of Elastic Solids.''
  
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In 1850, Maxwell left for [[University of Cambridge|Cambridge University]] and initially attended [[Peterhouse, Cambridge|Peterhouse]], but eventually left for [[Trinity College, Cambridge|Trinity College]] where he believed it was easier to obtain a [[fellowship]]. At Trinity, he was elected to the secret society known as the [[Cambridge Apostles]]. In November 1851, Maxwell studied under the tutor [[William Hopkins]] (nicknamed the "[[Wrangler (University of Cambridge)|wrangler]] maker"). A considerable part of the translation of his electromagnetism equations was accomplished during Maxwell's career as an undergraduate in Trinity.  
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In 1850, Maxwell left for [[University of Cambridge|Cambridge University]] and initially attended [[Peterhouse, Cambridge|Peterhouse]], but eventually left for [[Trinity College, Cambridge|Trinity College]] where he believed it would be easier to obtain a [[fellowship]]. In November 1851, Maxwell studied under the tutor [[William Hopkins]] (nicknamed the "[[Wrangler (University of Cambridge)|wrangler]] maker").  
  
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In 1854, Maxwell graduated with a degree as second wrangler in [[mathematics]] from Trinity (i.e. scoring second-highest in the final mathematics examination) and was declared equal with the senior wrangler of his year in the more exacting ordeal of the Smith's prize examination. For more than half of his relatively short life, he held a prominent position in the foremost rank of scientists, usually as a college professor. Immediately after taking his degree, he read to the Cambridge Philosophical Society a novel memoir, ''On the Transformation of Surfaces by Bending''. This is one of the few purely mathematical papers he published, and it exhibited at once to experts the full genius of its author. About the same time, his elaborate memoir, ''On [[Michael Faraday|Faraday]]'s Lines of Force'' appeared, in which he gave the first indication of some of the electrical investigations which culminated in the greatest work of his life.  
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In 1854, Maxwell graduated with a degree as second wrangler in [[mathematics]] from Trinity (i.e. scoring second-highest in the final mathematics examination) and was declared equal with the senior wrangler of his year in the more exacting ordeal of the Smith's prize examination. Immediately after taking his degree, he read to the Cambridge Philosophical Society a novel memoir, ''On the Transformation of Surfaces by Bending''. This is one of the few purely mathematical papers he published, and it exhibited at once to experts the full genius of its author. About the same time, his paper, ''On [[Michael Faraday|Faraday]]'s Lines of Force'' appeared, in which he gave the first indication of some of the electrical investigations which culminated in the greatest work of his life.  
  
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From 1855 to 1872, he published at intervals a series of valuable investigations connected with the ''Perception of Colour'' and ''Colour-Blindness'', for the earlier of which he received the [[Rumford medal]] from the Royal Society in 1860. The instruments which he devised for these investigations were simple and convenient in use. For example, [[Maxwell's discs]] were used to compare a variable mixture of three primary colours with a sample colour by observing the spinning "colour top." In 1856, Maxwell was appointed to the chair of Natural Philosophy in [[Marischal College]], [[Aberdeen, Scotland|Aberdeen]], which he held until the fusion of Aberdeen's two colleges in 1860.  
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In 1855, Maxwell was appointed to the chair of Natural Philosophy at [[Marischal College]], [[Aberdeen, Scotland|Aberdeen]].  In 1858 he married Katherine Mary Dewarin, the daughter of the principal of Marischal College. The couple had no children, but Maxwell often enjoyed the assistance of his wife in his duties. When Marischal merged with another college to form the University of Aberdeen, Maxwell's position was eliminated, but he soon found another, joining the teaching staff of Kings' College, London, as professor of natural philosophy.
  
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In 1859, he won the [[Adams prize]] in Cambridge for an original essay, ''On the Stability of Saturn's Rings'', in which he concluded the rings could not be completely solid or fluid. Maxwell demonstrated stability could ensue only if the rings consisted of numerous small solid particles, which he called "brickbats." He also mathematically disproved the nebular hypothesis (which stated that the [[solar system]] formed through the progressive [[condensation]] of a purely [[gaseous nebula]]), forcing the theory to account for additional portions of small solid particles.
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In 1859, Maxwell won the [[Adams prize]] in Cambridge for an original essay, ''On the Stability of Saturn's Rings'', in which he concluded the rings could not be completely solid or fluid. Maxwell demonstrated that the rings could only be stable if they consisted of numerous small solid particles, which he called "brickbats." He also mathematically disproved the nebular hypothesis (which stated that the [[solar system]] formed through the progressive [[condensation]] of a purely [[gaseous nebula]]), forcing the theory to account for additional portions of small solid particles.
  
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In 1860, he was a professor at [[King's College London]]. In 1861, Maxwell was elected to the [[Royal Society]]. He researched [[elasticity (solid mechanics)|elastic]] [[solid]]s and pure geometry during this time.
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On the foundation of an earlier paper written in 1855, he wrote in 1860 a paper "On the Theory of Compund Colours, which demonstrates that color blindness results from a deficiency in sensitivity to one of the three primary colors. For this paper, he was awarded the Rumsford Medal of the Royal Society. He was elected a member of the society a year later.
  
 
====Kinetic theory====
 
====Kinetic theory====
 
{{main|Maxwell-Boltzmann distribution}}
 
{{main|Maxwell-Boltzmann distribution}}
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One of Maxwell's greatest investigations was on the kinetic theory of gases. Originating with [[Daniel Bernoulli]], this theory was advanced by the successive labours of [[John Herapath]], [[John James Waterston]], [[James Joule]], and particularly [[Rudolf Clausius]], to such an extent as to put its general accuracy beyond a doubt; but it received enormous development from Maxwell, who in this field appeared as an experimenter (on the laws of gaseous friction) as well as a mathematician.  
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One of Maxwell's most important achievements was his contribution to kinetic theory of gases. Originating in its modern form with [[Daniel Bernoulli]] in the 18th century, this theory was advanced by the successive labors of [[John Herapath]], [[John James Waterston]], [[James Joule]], and particularly [[Rudolf Clausius]], but it received enormous development from Maxwell, who in this field appeared as an experimenter (on the laws of gaseous friction) as well as a mathematician. Joule had calculated the speed of molecules, but it was left in the lap of Clausius to explain why gases did not diffuse as rapidly as their speed would indicate. Clausius said that the slowness of a scent, for example, to travel in the air, was due to the many collisions among molecules that would resist its transit. The average distance a molecule would travel between the collisions Clausius called the "mean free path."
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Inspired by Clausius's work, Maxwell, using experimental data on viscocity, heat conduction and diffusion in gases,  along with a complex mathematical analysis of collisions of large numbers of molecules, calculated the mean free path of a molecule. This represented the first approximation of a measurement of atomic dimensions. Five years later, based on Maxwell's calculations, Josef Loschmidt published the first estimate of the actual size of a molecule.
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In 1866, Maxwell improved his treatment of the kinetic theory of gases, and published what is now called the Maxwell-Boltzmann distribution, which yields the fraction of gas molecules in a sample moving at a specified velocity at a given temperature.
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In 1865, Maxwell moved to the estate he inherited from his father in [[Glenlair]], [[Kirkcudbrightshire]], Scotland, and in 1868, resigned his Chair of Physics and Astronomy at King's College, London.
  
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In 1865, Maxwell moved to the estate he inherited from his father in [[Glenlair]], [[Kirkcudbrightshire]], Scotland. In 1868, he resigned his Chair of Physics and Astronomy at King's College, London.
 
  
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In 1866, he statistically formulated, independently of [[Ludwig Boltzmann]], the Maxwell-Boltzmann kinetic theory of gases. His formula, called the [[Maxwell distribution]], gives the fraction of gas molecules moving at a specified velocity at any given temperature. In the [[kinetic]] theory, temperatures and heat involve only molecular movement. This approach generalized the previously established laws of thermodynamics and explained existing observations and experiments in a better way than had been achieved previously. Maxwell's work on [[thermodynamics]] led him to devise the [[thought experiment]] that came to be known as [[Maxwell's demon]].
 
  
 
==== Electromagnetism====
 
==== Electromagnetism====
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[[Image:Postcard-from-Maxwell-to-Tait.jpg|thumb|right|175px|A postcard from Maxwell to [[Peter Guthrie Tait|Peter Tait]].]]
 
[[Image:Postcard-from-Maxwell-to-Tait.jpg|thumb|right|175px|A postcard from Maxwell to [[Peter Guthrie Tait|Peter Tait]].]]
  
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The greatest work of Maxwell's life was devoted to electricity. Maxwell's most important contribution was the extension and mathematical formulation of earlier work on [[electricity]] and [[magnetism]] by [[Michael Faraday]], [[André-Marie Ampère]], and others into a linked set of [[differential equation]]s (originally, 20 equations in 20 variables, later re-expressed in [[quaternion]]- and [[vector (spatial)|vector]]-based notations). These equations, which are now collectively known as [[Maxwell's equations]] (or occasionally, "Maxwell's Wonderful Equations"), were first presented to the Royal Society in 1864, and together describe the behaviour of both the [[electromagnetic field|electric and magnetic fields]], as well as their interactions with matter.
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The greatest work of Maxwell's life was devoted to electricity. Maxwell's most important contribution was the extension and mathematical formulation of earlier work on [[electricity]] and [[magnetism]] by [[Michael Faraday]], [[André-Marie Ampère]], and others into a linked set of [[differential equation]]s (originally, 20 equations in 20 variables, later re-expressed in [[quaternion]]- and [[vector (spatial)|vector]]-based notations). These equations, which are now collectively known as [[Maxwell's equations]], were first presented to the Royal Society in 1864, and together describe the behaviour of both the [[electromagnetic field|electric and magnetic fields]], as well as their interactions with matter. Maxwell formulated these equations by assuming the existence of a displacement current which takes place in the dielectric separating the plates of a capacitor. This was an original contribution of Maxwell, and enabled him to treat the space between conductors as a medium with certain properties rather than just a vacuum.
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Maxwell [[Electromagnetic wave equation|showed]] that the equations predict the existence of [[electromagnetic radiation|wave]]s of oscillating electric and magnetic fields that travel through empty space at a speed that could be predicted from simple electrical experiments; using the data available at the time, Maxwell obtained a velocity of 310,740,000 [[m/s]]. In his 1864 paper [[A Dynamical Theory of the Electromagnetic Field]], Maxwell wrote,
 
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:''The agreement of the results seems to show that light and magnetism are affections of the same substance, and that light is an electromagnetic disturbance propagated through the field according to electromagnetic laws''.
 
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Maxwell was proved correct, and his quantitative connection between light and electromagnetism is considered one of the great triumphs of 19th century physics.
 
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At that time, Maxwell believed that the propagation of light required a medium for the waves, dubbed the [[luminiferous aether]]. Over time, the existence of such a medium, permeating all space and yet apparently undetectable by mechanical means, proved more and more difficult to reconcile with experiments such as the [[Michelson-Morley experiment]]. Moreover, it seemed to require an absolute [[frame of reference]] in which the equations were valid, with the distasteful result that the equations changed form for a moving observer. These difficulties inspired [[Albert Einstein|Einstein]] to formulate the theory of [[special relativity]], and in the process Einstein dispensed with the requirement of a luminiferous aether.
 
  
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==Control theory==
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Maxwell [[Electromagnetic wave equation|showed]] that the equations predict the existence of [[electromagnetic radiation|wave]]s caused by oscillating electric and magnetic fields. Maxwell calculated the speed of such waves, finding that they would travel at a velocity of 310,740,000 [[m/s], roughly the same as the speed of light, which had already been measured. He concluded that light must be an electromagnetic phenomenon. Subsequent experimenters such as Heinrich Hertz and Oliver Lodge successfully generated and detected the electromagnetic waves predicted by Maxwell. Maxwell's quantitative connection between light and electromagnetism is considered one of the great triumphs of 19th century physics.
  
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Maxwell published a famous paper "On governors" in the Proceedings of Royal Society, vol. 16 (1867-1868). This paper is quite frequently considered a classical paper in the early days of control theory. (Please see publications below.)
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Maxwell's assumption that an actual medium existed that carried the light waves was later challenged by experiments failing to show any movement of the earth with respect to this medium, and, on a theoretical basis, by Einstein's theory of relativity, which assumes that light travels at the same speed irrespective of the velocity of the observer.  
  
 
===Later years, death and afterwards===
 
===Later years, death and afterwards===
 
[[Image:Tartan Ribbon.jpg|thumb|The first permanent colour photograph, taken by James Clerk Maxwell in 1861.]]
 
[[Image:Tartan Ribbon.jpg|thumb|The first permanent colour photograph, taken by James Clerk Maxwell in 1861.]]
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Maxwell also made contributions to the area of [[optics]] and colour vision, being credited with the discovery that colour [[photograph]]s could be formed using red, green, and blue filters. He had the [[photographer]] [[Thomas Sutton (photographer)|Thomas Sutton]] photograph a [[tartan]] ribbon three times, each time with a different colour filter over the lens. The three images were developed and then projected onto a screen with three different projectors, each equipped with the same colour filter used to take its image. When brought into focus, the three images formed a full colour image. The three photographic plates now reside in a small museum at 14 India Street, Edinburgh, the house where Maxwell was born.
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Maxwell also made contributions to the area of [[optics]] and color vision, being credited with the discovery that coloor [[photograph]]s could be formed using red, green, and blue filters. He had the [[photographer]] [[Thomas Sutton (photographer)|Thomas Sutton]] photograph a [[tartan]] ribbon three times, each time with a different colour filter over the lens. The three images were developed and then projected onto a screen with three different projectors, each equipped with the same colour filter used to take its image. When brought into focus, the three images formed a full colour image. The three photographic plates now reside in a small museum at 14 India Street, Edinburgh, the house where Maxwell was born.
  
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Maxwell's work on [[colour blindness]] won him the [[Rumford Medal]] by the [[Royal Society of London]]. He wrote an admirable textbook of the ''Theory of Heat'' (1871), and an excellent elementary treatise on ''Matter and Motion'' (1876). Maxwell was also the first to make explicit use of [[dimensional analysis]], also in 1871.
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Maxwell wrote an admirable textbook, ''Theory of Heat'' (1871), and an elementary treatise, ''Matter and Motion'' (1876), which serves as an introduction to physics.  
  
 
[[Image:JamesClerkMaxwell-KatherineMaxwell-1869.jpg|thumb|left|James and Katherine Maxwell, 1869.]]
 
[[Image:JamesClerkMaxwell-KatherineMaxwell-1869.jpg|thumb|left|James and Katherine Maxwell, 1869.]]
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In 1871, he was the first [[Cavendish Professor of Physics]] at [[University of Cambridge|Cambridge]]. Maxwell was put in charge of the development of the [[Cavendish Laboratory]]. He supervised every step of the progress of the building and of the purchase of the very valuable collection of apparatus paid for by its generous founder, the [[William Cavendish, 7th Duke of Devonshire|7th Duke of Devonshire]] (chancellor of the university, and one of its most distinguished alumni). One of Maxwell's last great contributions to science was the editing (with copious original notes) of the electrical researches of [[Henry Cavendish]], from which it appeared that Cavendish researched such questions as the [[mean]] [[density]] of the earth and the composition of water, among other things.
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In 1871, Maxwell was appointed the first [[Cavendish Professor of Physics]] at [[University of Cambridge|Cambridge]]. Maxwell was put in charge of the development of the [[Cavendish Laboratory]]. One of Maxwell's last contributions was the editing (with copious original notes) of the electrical researches of [[Henry Cavendish]], from which it appeared that Cavendish researched such questions as the [[mean]] [[density]] of the earth and the composition of water.
  
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Maxwell married Katherine Mary Dewar when he was 27 years of age, but they had no children. He died in Cambridge of abdominal cancer at the age of 48. He had been a devout Christian his entire life.  Maxwell is buried at [[Parton, Dumfries and Galloway|Parton]] Kirk, near [[Castle Douglas]] in [[Galloway]], [[Scotland]].
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Much of Maxwell's time was consumed with the editing of Cavendish's papers. This project took him away from what might have been more fruitful ventures in pure science. He died in Cambridge of abdominal cancer at the age of 48. He is buried at [[Parton, Dumfries and Galloway|Parton]] Kirk, near [[Castle Douglas]] in [[Galloway]], [[Scotland]].
  
 
The extended biography ''The Life of James Clerk Maxwell'', by his former schoolfellow and lifelong friend Professor [[Lewis Campbell]], was published in 1882 and his collected works, including the series of articles on the properties of matter, such as ''Atom'', ''Attraction'', ''Capillary Action'', ''Diffusion'', ''Ether'', etc., were issued in two volumes by the [[Cambridge University Press]] in 1890.
 
The extended biography ''The Life of James Clerk Maxwell'', by his former schoolfellow and lifelong friend Professor [[Lewis Campbell]], was published in 1882 and his collected works, including the series of articles on the properties of matter, such as ''Atom'', ''Attraction'', ''Capillary Action'', ''Diffusion'', ''Ether'', etc., were issued in two volumes by the [[Cambridge University Press]] in 1890.
  
 
===Personality===
 
===Personality===
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From the start of his childhood, religion touched all aspects of Maxwell's life. Both his father and mother were devout churchgoers (Presbyterian and Episcopalian) and instilled a strong faith in their son. All information available suggests that neither in his adolescence, nor in his later years, did Maxwell ever reject the fundamental principles of his Christian faith. Ivan Tolstoy, author of one of Maxwell's biographies, remarked at the frequency with which scientists writing short biographies on Maxwell often omit the subject of his religion. It is impossible, however, to fully understand the man of James Clerk Maxwell without considering his faith. Tolstoy further suggests that such an "introspective, sensitive and lonely adolescent," would have relied on his religious beliefs for comfort.
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From the start of his childhood, religion touched all aspects of Maxwell's life. Both his father and mother were devout churchgoers (Presbyterian and Episcopalian). The occasional reference to the divine in his writings indicates that his faith was a guiding force in his life.
  
 
As a great lover of British poetry, Maxwell memorized poems and wrote his own. The best known is ''Rigid Body Sings'' closely based on ''[[Comin' Through the Rye]]'' by [[Robert Burns]], which he apparently used to sing while accompanying himself on a guitar. It has the immortal opening lines[http://www.haverford.edu/physics-astro/songs/rigid.htm]:  
 
As a great lover of British poetry, Maxwell memorized poems and wrote his own. The best known is ''Rigid Body Sings'' closely based on ''[[Comin' Through the Rye]]'' by [[Robert Burns]], which he apparently used to sing while accompanying himself on a guitar. It has the immortal opening lines[http://www.haverford.edu/physics-astro/songs/rigid.htm]:  
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== References ==
 
== References ==
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* Abbott, David, ed., The BIographical Dictionary of Scientists. New York: Peter Bedrick Books, 1984. ISBN 0195210832.
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* Gillispie, C.C., ed., Dictionary of Scientific Biography. New York: Charles Scribner's Sons, 1973. ISBN 0684313200.
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* Porter, R., ed., The Biographical Dictionary of Scientists, 2nd edition. New York: Oxford University Press, 1994.
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Revision as of 02:37, 21 April 2007

James Clerk Maxwell

James Clerk Maxwell.png
James Clerk Maxwell
Born

13 June, 1831
Edinburgh, Scotland

Died 5 November, 1879

Cambridge, England

Residence Scotland
Nationality Scottish
Field Mathematician and physicist
Alma mater University of Cambridge
Known for Maxwell's Equations, The Maxwell Distribution
Notable prizes Rumford Medal, Adams Prize
Religious stance Christian

James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish mathematician and theoretical physicist. He developed a mathematical expression that described the actions of electricty and magnetism and their interrelationship, and from these predicted the existence of electromagnetic waves traveling at the speed of light. Maxwell was also the first to peer into the dimensions of the molecular world by calculating the average distance a gas molecule travels before it hits another molecule. Maxwell also produced the first color photograph.

Biography

Early life and education

James Clerk Maxwell was born on June 13, 1831 in Edinburgh, Scotland, to John Clerk and Frances (née Cay) Maxwell. His birthplace, at 15 India Street, is now the location of the International Centre for Mathematical Sciences.

Maxwell grew up on his father's estate in Dumfrieshire in the Scottish countryside. Maxwell's parents quickly recognized their son's inquisitive nature. His mother took responsibility for his early education, which in Victorian times was largely the job of the women of the house. She died in 1839, however, when Maxwell was only eight. His father then undertook the education of his son with the aid of his sister-in-law Jane Cay, both of whom played pivotal roles in Maxwell's life. His formal education began under the guidance of a hired tutor, but finding this arrangement less than satisfactory, John Maxwell sent his son to the Edinburgh Academy.

Maxwell was captivated by geometry at an early age. Much of his talent went unnoticed however, and his academic work remained unremarkable until, in 1845 at the age of 13, he won the school's mathematical medal, and first prizes for English and for English verse. His first piece of original work, at the age of 14 was a paper describing mechanical means of drawing mathematical curves with a piece of twine, and properties of ellipses and curves with more than two foci. This work, Oval Curves, was published in an issue of the Royal Society of Edinburgh, and although it shows the curiosity of Maxwell at a young age, it is important to note that the work itself was not mathematically profound. Unlike other great minds, such as Gauss, Pascal or Mozart, Maxwell was not a child prodigy. Rather, his genius would slowly mature.

Middle years

A young Maxwell at university.

Maxwell left the Academy in 1847 and enrolled at the University of Edinburgh. He completed his studies at Edinburgh in natural philosophy, moral philosophy, and mental philosophy under Sir William Hamilton, 9th Baronet. In his eighteenth year he contributed a paper to Transactions of the Royal Society of Edinburgh, On the Equilibrium of Elastic Solids.

In 1850, Maxwell left for Cambridge University and initially attended Peterhouse, but eventually left for Trinity College where he believed it would be easier to obtain a fellowship. In November 1851, Maxwell studied under the tutor William Hopkins (nicknamed the "wrangler maker").

In 1854, Maxwell graduated with a degree as second wrangler in mathematics from Trinity (i.e. scoring second-highest in the final mathematics examination) and was declared equal with the senior wrangler of his year in the more exacting ordeal of the Smith's prize examination. Immediately after taking his degree, he read to the Cambridge Philosophical Society a novel memoir, On the Transformation of Surfaces by Bending. This is one of the few purely mathematical papers he published, and it exhibited at once to experts the full genius of its author. About the same time, his paper, On Faraday's Lines of Force appeared, in which he gave the first indication of some of the electrical investigations which culminated in the greatest work of his life.

In 1855, Maxwell was appointed to the chair of Natural Philosophy at Marischal College, Aberdeen. In 1858 he married Katherine Mary Dewarin, the daughter of the principal of Marischal College. The couple had no children, but Maxwell often enjoyed the assistance of his wife in his duties. When Marischal merged with another college to form the University of Aberdeen, Maxwell's position was eliminated, but he soon found another, joining the teaching staff of Kings' College, London, as professor of natural philosophy.

In 1859, Maxwell won the Adams prize in Cambridge for an original essay, On the Stability of Saturn's Rings, in which he concluded the rings could not be completely solid or fluid. Maxwell demonstrated that the rings could only be stable if they consisted of numerous small solid particles, which he called "brickbats." He also mathematically disproved the nebular hypothesis (which stated that the solar system formed through the progressive condensation of a purely gaseous nebula), forcing the theory to account for additional portions of small solid particles.

On the foundation of an earlier paper written in 1855, he wrote in 1860 a paper "On the Theory of Compund Colours, which demonstrates that color blindness results from a deficiency in sensitivity to one of the three primary colors. For this paper, he was awarded the Rumsford Medal of the Royal Society. He was elected a member of the society a year later.

Kinetic theory

One of Maxwell's most important achievements was his contribution to kinetic theory of gases. Originating in its modern form with Daniel Bernoulli in the 18th century, this theory was advanced by the successive labors of John Herapath, John James Waterston, James Joule, and particularly Rudolf Clausius, but it received enormous development from Maxwell, who in this field appeared as an experimenter (on the laws of gaseous friction) as well as a mathematician. Joule had calculated the speed of molecules, but it was left in the lap of Clausius to explain why gases did not diffuse as rapidly as their speed would indicate. Clausius said that the slowness of a scent, for example, to travel in the air, was due to the many collisions among molecules that would resist its transit. The average distance a molecule would travel between the collisions Clausius called the "mean free path."

Inspired by Clausius's work, Maxwell, using experimental data on viscocity, heat conduction and diffusion in gases, along with a complex mathematical analysis of collisions of large numbers of molecules, calculated the mean free path of a molecule. This represented the first approximation of a measurement of atomic dimensions. Five years later, based on Maxwell's calculations, Josef Loschmidt published the first estimate of the actual size of a molecule.

In 1866, Maxwell improved his treatment of the kinetic theory of gases, and published what is now called the Maxwell-Boltzmann distribution, which yields the fraction of gas molecules in a sample moving at a specified velocity at a given temperature.

In 1865, Maxwell moved to the estate he inherited from his father in Glenlair, Kirkcudbrightshire, Scotland, and in 1868, resigned his Chair of Physics and Astronomy at King's College, London.


Electromagnetism

A postcard from Maxwell to Peter Tait.

The greatest work of Maxwell's life was devoted to electricity. Maxwell's most important contribution was the extension and mathematical formulation of earlier work on electricity and magnetism by Michael Faraday, André-Marie Ampère, and others into a linked set of differential equations (originally, 20 equations in 20 variables, later re-expressed in quaternion- and vector-based notations). These equations, which are now collectively known as Maxwell's equations, were first presented to the Royal Society in 1864, and together describe the behaviour of both the electric and magnetic fields, as well as their interactions with matter. Maxwell formulated these equations by assuming the existence of a displacement current which takes place in the dielectric separating the plates of a capacitor. This was an original contribution of Maxwell, and enabled him to treat the space between conductors as a medium with certain properties rather than just a vacuum.

Maxwell showed that the equations predict the existence of waves caused by oscillating electric and magnetic fields. Maxwell calculated the speed of such waves, finding that they would travel at a velocity of 310,740,000 [[m/s], roughly the same as the speed of light, which had already been measured. He concluded that light must be an electromagnetic phenomenon. Subsequent experimenters such as Heinrich Hertz and Oliver Lodge successfully generated and detected the electromagnetic waves predicted by Maxwell. Maxwell's quantitative connection between light and electromagnetism is considered one of the great triumphs of 19th century physics.

Maxwell's assumption that an actual medium existed that carried the light waves was later challenged by experiments failing to show any movement of the earth with respect to this medium, and, on a theoretical basis, by Einstein's theory of relativity, which assumes that light travels at the same speed irrespective of the velocity of the observer.

Later years, death and afterwards

The first permanent colour photograph, taken by James Clerk Maxwell in 1861.

Maxwell also made contributions to the area of optics and color vision, being credited with the discovery that coloor photographs could be formed using red, green, and blue filters. He had the photographer Thomas Sutton photograph a tartan ribbon three times, each time with a different colour filter over the lens. The three images were developed and then projected onto a screen with three different projectors, each equipped with the same colour filter used to take its image. When brought into focus, the three images formed a full colour image. The three photographic plates now reside in a small museum at 14 India Street, Edinburgh, the house where Maxwell was born.

Maxwell wrote an admirable textbook, Theory of Heat (1871), and an elementary treatise, Matter and Motion (1876), which serves as an introduction to physics.

James and Katherine Maxwell, 1869.

In 1871, Maxwell was appointed the first Cavendish Professor of Physics at Cambridge. Maxwell was put in charge of the development of the Cavendish Laboratory. One of Maxwell's last contributions was the editing (with copious original notes) of the electrical researches of Henry Cavendish, from which it appeared that Cavendish researched such questions as the mean density of the earth and the composition of water.

Much of Maxwell's time was consumed with the editing of Cavendish's papers. This project took him away from what might have been more fruitful ventures in pure science. He died in Cambridge of abdominal cancer at the age of 48. He is buried at Parton Kirk, near Castle Douglas in Galloway, Scotland.

The extended biography The Life of James Clerk Maxwell, by his former schoolfellow and lifelong friend Professor Lewis Campbell, was published in 1882 and his collected works, including the series of articles on the properties of matter, such as Atom, Attraction, Capillary Action, Diffusion, Ether, etc., were issued in two volumes by the Cambridge University Press in 1890.

Personality

From the start of his childhood, religion touched all aspects of Maxwell's life. Both his father and mother were devout churchgoers (Presbyterian and Episcopalian). The occasional reference to the divine in his writings indicates that his faith was a guiding force in his life.

As a great lover of British poetry, Maxwell memorized poems and wrote his own. The best known is Rigid Body Sings closely based on Comin' Through the Rye by Robert Burns, which he apparently used to sing while accompanying himself on a guitar. It has the immortal opening lines[1]:

Gin a body meet a body
Flyin' through the air.
Gin a body hit a body,
Will it fly? And where?

A collection of his poems was published by his friend Lewis Campbell in 1882.

Honours

Maxwell was ranked #24 on Michael H. Hart's list of the most influential figures in history and #91 on the BBC poll of the 100 Greatest Britons.

Homage

“ [The work of Maxwell]...[is] the most profound and the most fruitful that physics has experienced since the time of Newton. ”

—Albert Einstein, The Sunday Post[1]

  • The maxwell (Mx), a compound derived CGS unit measuring magnetic flux (commonly abbreviated as f).
  • Maxwell Montes, a mountain range on Venus, one of only three features on the planet that are not given female names.
  • The James Clerk Maxwell Telescope, the largest sub-mm astronomical telescope in the world, with a diameter of 15 metres.
  • The 1977 James Clerk Maxwell building of the University of Edinburgh, housing the schools of mathematics, physics, computer science and meteorology.
  • The James Clerk Maxwell building at the Waterloo campus of King's College London, in commemoration of him being Professor of Natural Philosophy at King's from 1860 to 1865. The university also has a chair in Physics named after him, and a society for undergraduate physicists.
  • The £4 million James Clerk Maxwell Centre of the Edinburgh Academy was opened in 2006 to mark his 175th anniversary.
  • James Clerk Maxwell Road in Cambridge, which runs along one side of the Cavendish Laboratory.
  • The University of Salford's main building has also been named after him.
  • James Clerk Maxwell was featured in the 1995 SNES game Tales of Phantasia as a summon that can aid the party in battle. His ability consisted of electromagnetic spheres that attacked the enemy.

Publications

See also

References
ISBN links support NWE through referral fees

  • Abbott, David, ed., The BIographical Dictionary of Scientists. New York: Peter Bedrick Books, 1984. ISBN 0195210832.
  • Gillispie, C.C., ed., Dictionary of Scientific Biography. New York: Charles Scribner's Sons, 1973. ISBN 0684313200.
  • Porter, R., ed., The Biographical Dictionary of Scientists, 2nd edition. New York: Oxford University Press, 1994.


  1. ↑ McFall, Patrick "Brainy young James wasn't so daft after all" in The Sunday Post, April 23 2006

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Mathematics

Treatise On Electricity And Magnetism - 1873 Edition

Versions of Maxwell's 1873 treatise readable online

Supplementary material for understanding Maxwell's 1873 treatise


Persondata
NAME Maxwell, James Clerk
ALTERNATIVE NAMES
SHORT DESCRIPTION mathematical physicist
DATE OF BIRTH 13 June 1831
PLACE OF BIRTH Edinburgh
DATE OF DEATH 5 November 1879
PLACE OF DEATH Cambridge

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