James Clerk Maxwell

James Clerk Maxwell (Edinburgh, June 13, 1831 – Cambridge, November 5, 1879) was a Scottish physicist best known for his formulation of electromagnetic theory and the statistical theory of gases. He is regarded by most modern physicists as the scientist of the 19th century who had the greatest influence on 20th-century physics, and he is ranked with Isaac Newton, Albert Einstein and the creators of quantum mechanics Werner Heisenberg, Edwin Schrödinger, and Paul Dirac.

He gave his name to the Maxwell equations, the Maxwell-Boltzmann distribution, and the unit of magnetic flux, the maxwell.

Biography

Family

James Clerk Maxwell came from two prominent and affluent Scottish families, the Maxwells and the Clerks, both of lower nobility and heavily interrelated. James' father, John, was a younger paternal grandchild of Sir George Clerk, and accordingly was named John Clerk. John added legally the name Maxwell later, after he had inherited the Maxwell's Middlebie estate in the Galloway area (in the South-West of Scotland, 10 km North of Castle Douglas, the market-town, and about 70 km West from the town of Middlebie, in Dumfriesshire).

After marrying Frances Cay in 1826, John Clerk Maxwell and his bride moved from Edinburgh to the Middlebie estate. He and Frances built a country house there, named Glenlair. The house was in a rather isolated spot, even for Scottish standards, far removed from any cities, the closed cities being Glasgow (110 km to the North, a full day's journey at the time) and Edinburgh, which was two whole days of travel.

Early youth

James was born in Edinburgh, where his parents had gone to ensure proper medical attention at his birth. James was the first son of his mother, who had lost previously a daughter of a few months old. Mrs. Clerk Maxwell had the relatively advanced age of forty when she gave birth to James. Soon after the birth the family went back to the Glenlair House. James, who remained an only child, was brought up in the Galloway region, where he played with the local children and acquired a thick Scottish accent, in spite of his upperclass descent. He would never quite lose his accent.

Maxwell's mother died in 1839 from abdominal cancer, the same disease to which Maxwell was to succumb at exactly the same age of forty-eight years. James grew up alone with his father with whom he had a happy and close relationship. At young age James received private lessons from a dull and uninspired tutor, who claimed that James was slow at learning, though in fact he was very inquisitive and had a phenomenal memory. At the age of ten James was sent to the Edinburgh Academy to receive a proper education. During term time, he was living either with his mother's sister Jane Cay, who was unmarried, or with his father's sister Isabella, the widow of James Wedderburn. Both aunts lived in Edinburgh. At the academy he became a life-long friend of Peter Guthrie Tait, who would become a well-known scientist too and one of the advocates of Hamilton's quaternion theory. In the beginning James had a difficult time at school because of his Galloway accent and because he wore strange, but practical, clothes, designed by his father.

At school Maxwell was showing unusual mathematical ability, and at the age of fifteen invented by analogy with the construction of an ellipse a way of drawing ovals using a piece of string. This work was published in the Proceedings of the Royal Society of Edinburgh, and although not an important paper, it is remarkable for such a young author.

Student days

At the age of sixteen Maxwell entered Edinburgh University. He was not unusually young to enter a Scottish Unversity. At that time these were hybrids between secondary schools and universities as we now know them. Maxwell studied mathematics, philosophy, and physics and left after three years without graduating to go up to Cambridge, at first to Peterhouse College, which housed many Scotsmen, and after one term to Trinity College.

By the time he entered Cambridge University, Maxwell was very knowledgeable about English literature and was himself a reasonably good poet. And, of course, he had a vast knowledge of mathematics and physics. In his first year at Cambridge he had to undertake systematic studies, as any student, although he had already a few papers, one of them a valuable one on elasticity. His tutor, the mathematician Wiliam Hopkins, noted his strong geometrical insight but also that in analysis his powers were somewhat less. Maxwell followed the lectures by Stokes and met William Thomson again, whom he had first met while at Edinburgh University.

In 1854 Maxwell was second wrangler (second place at the competitive exam the "mathematical tripos") and first Smith's prizeman (the Smith's Prize is a prestigious competitive award for an essay that incorporates original research). He was elected to a fellowship at his college, Trinity, and started serious research on two of his favorite topics, color theory and electromagnetism.

The scientist

Clerk Maxwell kept his fellowship at Trinity for a short time only. Because his father's health was deteriorating, he looked for, and found, a professorship in Scotland. He hoped that the long vacations of Scottish universities would permit him to spend many months each year at his beloved Glenlair with his father. He became professor of natural philosophy at Marischal College, Aberdeen, but before the appointment was announced his father died, in April 1856. In June 1858, Maxwell married Katherine Mary Dewar, the daughter of the principal of Marischal College and seven years James' senior. The marriage remained childless.

In 1860 the King's College and Marischal College, both in Aberdeen, merged forming the nucleus of what would become Aberdeen University. Maxwell was made redundant, even though he was the son-in-law of one of the principals.

Twice Maxwell was nominated for a Royal Medal of the Royal Society on for his work on the perception of color, and twice he was passed. But a nomination in May 1860 by Stokes and William Hallowes Miller (Cambridge professor of mineralogy) for the Rumford Medal was successful.

Maxwell's most important work in Aberdeen was a theoretical study on the nature of Saturn's rings. He proved that the rings must consist of myriad small particles, or moonlets, each in their own orbit around the planet and that the ring could not be solid. Maxwell was awarded the £130 Adams Prize in 1859 for his essay On the Stability of Saturn's Rings.

After made redundant in Aberdeen, Maxwell applied for a vacancy at the University of Edinburgh, but he was turned down in favour of his school friend Tait. He then was appointed to the professorship of natural philosophy at King's College, London.

Scientific work

Color Theory

Clerk Maxwell started studies on color vision while still at Edinburgh, under guidance of Professor James David Forbes. Fundamental progress on color theory—a subdiscipline of physiological optics—had been made earlier by Thomas Young, who had arrived at the conception of three fundamental colors, red, green, and blue. Maxwell continued Young's investigations by studying color perception with a spinning top that allowed quantitatively measuring of the colors being mixed. Maxwell's work contributed importantly to the unraveling of the mysteries surrounding color vision. As a spin-off of his researches, he was able to show the first ever color slide, which he projected at the Royal Institution on 17 May 1861. A hundred years later it was found that Maxwell was lucky that his strategy in designing the slide worked, because ultraviolet acted as a proxy for red in the recording stage, a fact that Maxwell was not aware of. In any case, his slide projection greatly impressed his audience.

The work of Young and Maxwell is known today to any computer user who is trying to create his own colors by the RGB color scheme.

Saturn's rings

The planet Saturn has a flat circular ring, first observed by Galileo Galilei in 1610, but not understood by him. The Dutch physicist Christiaan Huygens recognized it as a ring in 1655 and twenty years later Giovanni Domenico Cassini saw that there were actually two rings. In 1850 the Harvard astronomer George Phillips Bond discovered a dark obscure ring interior to the two rings known since the 17th century. On a visit to Europe in 1851 Bond spoke about his discovery in Cambridge where he aroused the interest of James Challis, the Plumian professor of astronomy. The mechanical stability of the ring was hardly understood at that time. The great Laplace had studied it and found that a solid uniform ring would be dynamically unstable and could not revolve permanently about the planet.

Challis set the stability of Saturn's rings as the subject of the 1857 Adams Prize essay. This prize had been established in 1848 by a few members of St. John's college of Cambridge University in honor of John Couch Adams' prediction of the existence of the planet Neptune. Only Cambridge graduates could enter the competition. Clerk Maxwell took up the challenge and submitted his essay on 16 December 1856; Maxwell's was the only submission.

In the first part of his essay he showed that the rings cannot be homogeneously solid, because, in accordance with Laplace's earlier finding, they would be unstable. In the second part of his prize essay Maxwell assumed that the rings were fluid (but not at rest because they would then collapse into Saturn). He showed that liquid rings would soon break up in pieces by internal friction and therefore he ends up by the assumption that the only system of rings which can exist is one composed of an indefinite number of unconnected particles, revolving around the planet with different velocities according to their respective distances. This is the correct description as confirmed by several modern space probes.

Maxwell was awarded the Adams prize on 30 May 1857. Two years later he summarized his more than 80 pages essay in a short article.

(To be continued)

External link

Life of James Clerk Maxwell by Lewis Campbell (1882)

References and notes

• I. Tolstoy, James Clerk Maxwell, a biography. Edinburgh: Canongate; 1981.
• B. Mahon, The man who changed everything. Chichester: Wiley; 2003