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James Clerk Maxwell
James Clerk Maxwell (June 13, 1831–November 5, 1879) was a Scottish prominent physicist, born in Edinburgh.
Maxwell is generally regarded as the nineteenth century scientist who had the greatest influence on twentieth century physics, making contributions to the fundamental models of nature. In 1931, on the centennial anniversary of Maxwell's birth, Einstein described Maxwell's work as the "most profound and the most fruitful that physics has experienced since the time of Newton."
Contributions:
- From 1855 to 1872, Maxwell 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.
- Maxwell obtained in 1859 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 obtain only if the rings consisted of numerous small solid particles. He also mathematically disproved the nebular hypothesis (which stated that solar system formed through the progressive condensation of a purely gaseous nebula), forcing the theory to account for additional portions of small solid particles.
- In 1866, he statistically formulated, independent of Ludwig Boltzmann, the Maxwell-Boltzmann kinetic theory of gases. His formula, called the Maxwell-Boltzmann 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 previous laws of thermodynamics, explaining the observations and experiments in a better way. Maxwell's work on thermodynamics led him to devise the thought experiment that came to be known as Maxwell's demon.
- Later in his life, Maxwell also made contributions to the area of optics and colour vision, being credited with the discovery that colour 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 register, the three images formed a full colour image. The resulting image's colours were somewhat unnatural, because the filters passed invisible wavelengths of light, but the principle was sound. The three photographic plates now reside in a small museum at 14 India Street, Edinburgh, the house where Maxwell was born.
- However, the great 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 behavior of both the electric and magnetic fields, as well as their interactions with matter.
Furthermore, Maxwell demonstrated that electric and magnetic forces are two complementary aspects of electromagnetism. He showed that electric and magnetic fields travel through empty space, in the form of waves, at a constant velocity of 3.0 × 108 m/s. He also proposed that light was a form of electromagnetic radiation.
- This velocity is so nearly that of light, that it seems we have strong reason to conclude that light itself (including radiant heat, and other radiations if any) is an electromagnetic disturbance in the form of waves propagated through the electromagnetic field according to electromagnetic laws.
Maxwell proved correct, and his quantitative connection between light and electromagnetism is considered one of the great triumphs of 19th century physics.
The fundamental idea of charge conservation is also contained in Maxwell's equations.
Maxwell had unified the work of previous electromagnetic and optical experiments at last, reducing their experimental results and observations into a series of mathematical equations. These equations (as well as the Maxwell distribution) have proven extremely useful in physics ever since. They hold true in all cases and therefore yielded several new laws of electromagnetism and optics, most importantly electromagnetic radiation. The equations are fundamental to radio and television, and can be used for studying X-rays, gamma rays, infrared rays, and other forms of radiation.
- Rumford Medal from the Royal Society in 1860
- Maxwell, James Clerk, "On the Description of Oval Curves, and those having a plurality of Foci". Procedure of the Royal Society of Edinburgh, Vol. ii. 1846.
- Maxwell, James Clerk, "Illustrations of the Dynamical Theory of Gases". 1860.
- Maxwell, James Clerk, "On Physical Lines of Force". 1861.
- Maxwell, James Clerk, "A Dynamical Theory of the Electromagnetic Field". 1865.(Maxwell's equations)
- Maxwell, James Clerk, "Theory of Heat". 1871.
- Maxwell, James Clerk, "A Treatise on Electricity and Magnetism". Clarendon Press, Oxford. 1873.
- Maxwell, James Clerk, Theory of Heat, 3rd ed. (1872, reprinted 1970)
- Maxwell, James Clerk, "Molecules. Nature, September, 1873.
- Maxwell, James Clerk, "On the Results of Bernoulli's Theory of Gases as Applied to their Internal Friction, their Diffusion, and their Conductivity for Heat".
- W.D. Niven (ed.), The Scientific Papers of James Clerk Maxwell, 2 vol. (1890, reissued 2 vol. in 1, 1965).
- Maxwell, James Clerk, A Treatise on Electricity and Magnetism, 3rd ed., 2 vol. (1892, reissued 1954).
- Glenlair Today
- Wolfram Research's Maxwell
- MacTutor's Maxwell
- Victorian Web's Maxwell
- Maxwell and the Christian Proposition
- 1911 Britannica Maxwell
- The James Clerk Maxwell Foundation
- Lewis Campbell and William Garnett, The Life of James Clerk Maxwell (1882, reprinted 1969).
- C.W.F. Everitt, James Clerk Maxwell: Physicist and Natural Philosopher (1975).
- Ivan Tolstoy, James Clerk Maxwell (1981).
- Martin Goldman, The Demon in the Aether (1983).
- R.a.r. Tricker, The Contributions of Faraday and Maxwell to Electrical Science (1966).
- Edmund Whittaker, A History of the Theories of Aether and Electricity, rev. and enlarged ed., 2 vol. (1951–53, reprinted 1987).
- Jed Z. Buchwald, From Maxwell to Microphysics: Aspects of Electromagnetic Theory in the Last Quarter of the Nineteenth Century (1985).
This article is licensed under the GNU Free Documentation License. It uses material from Wikipedia Encyclopedia article "James Clerk Maxwell"
