James
Clerk Maxwell
(1831-1879)
James
Clerk Maxwell was one of the greatest scientists of the 19th
century. He is best known for the formulation of the theory
of electromagnetism and in making the connection between light
and electromagnetic waves. He also made significant contributions
in the areas of physics, mathematics, astronomy and engineering.
He considered by many as the father of modern physics.
Maxwell
was born in Edinburgh, Scotland in 1831. Even though most of his
formal higher education took place in London, he was always drawn
back to his family home in the hills of Scotland. As a young child,
Maxwell was fascinated with geometry and mechanical models. When
he was only 14 years old, he published his first scientific paper
on the mathematics of oval curves and ellipses that he traced
with pins and thread. Maxwell continued to publish papers on a
variety of subjects. These included the mathematics of human perception
of colors, the kinetic theory of gasses, the dynamics of a spinning
top, theories of soap bubbles, and many others.
Maxwell's
early education took place at Edinburgh Academy and the University
of Edinburgh. In 1850 he went on to study at the University of
Cambridge and, upon graduation from Cambridge, Maxwell became
a professor of natural philosophy at Marischal College in Aberdeen
until 1860. He then moved to London to become a professor of natural
philosophy and astronomy at King's College. In 1865, Maxwell's
father died and he returned to the family home in Scotland to
devote his time to research. In 1871 he accepted a position as
the first professor of experimental physics at Cambridge where
he set up the world famous Cavendish Laboratory in 1874.
While
at Aberdeen, Maxwell was challenged by the subject of the Adams
Prize of 1857: the motion of Saturn's rings. He had previously
thought and theorized about the nature of the rings when he was
only 16 years old. He decided to compete for the prize, and the
next two years were taken up with developing a theory to explain
the physical composition of the rings. He was finally able to
demonstrate, by purely mathematical reasoning, that the stability
of rings could only be achieved if they consisted of numerous
small particles. His theory won him the prize and, more significantly,
nearly a hundred years later, the Voyager 1 space probe proved
his theory right.
Much
of modern technology has been developed from the basic principles
of electromagnetism formulated by Maxwell. The field of electronics,
including the telephone, radio, television, and radar, stem from
his discoveries and formulations. While Maxwell relied heavily
on previous discoveries about electricity and magnetism, he also
made a significant leap in unifying the theories of magnetism,
electricity, and light. His revolutionary work lead to the development
of quantum physics in the early 1900's and to Einstein's theory
of relativity.
Maxwell
began his work in electromagnetism by extending Michael Faraday's
theories of electricity and magnetic lines of force. He then began
to see the connections between the approaches of Faraday, Reimann
and Gauss. As a result, he was able to derive one of the most
elegant theories yet formulated. Using four equations, he described
and quantified the relationships between electricity, magnetism
and the propagation of electromagnetic waves. The equations are
now known as Maxwell's Equations.
One
of the first things that Maxwell did with the equations was to
calculate the speed of an electromagnetic wave and found that
the speed of an electromagnetic wave was almost identical to the
speed of light. Based on this discovery, he was the first to propose
that light was an electromagnetic wave. In 1862 Maxwell wrote:
"We
can scarcely avoid the conclusion that light consists in the transverse
undulations of the same medium which is the cause of electric
and magnetic phenomena."
This
was a remarkable achievement, for it not only unifies the theories
of electricity and magnetism, but of optics as well. Electricity,
magnetism and light can now be understood as aspects of a single
phenomenon: electromagnetic waves.
Maxwell
also described the thermodynamic properties of gas molecules using
statistical mechanics. His improvements to the kinetic theory
of gases included showing that temperature and heat are caused
only by molecular movement. Though Maxwell did not originate the
kinetic theory, he was the first to apply probability and statistics
to describe temperature changes at the molecular level. His theory
is still widely used by scientists as a model for rarefied gases
and plasmas.
Maxwell
also contributed to the development of color photography. His
analysis of color perception led to his invention of the trichromatic
process. By using red, green and blue filters he created the first
color photograph. The trichromatic process is the basis modern
color photography.
Maxwell's
particular gift was in applying mathematical reasoning in solving
complex theoretical problems. Maxwell's Electromagnetic Equations
are perfect examples of how mathematics can be used to provide
relatively simple and elegant explanations of the complex mysteries
of the universe. Richard Feynman wrote of Maxwell:
"From
a long view of the history of mankind, seen from, say, ten thousand
years from now, there can be little doubt that the most significant
event of the 19th century will be judged as Maxwell's discovery
of the laws of electrodynamics."
Maxwell
continued his work at the Cavendish Laboratory until illness forced
him to resign in 1879. He returned to Scotland and died soon afterwards.
He was buried with little ceremony in a small churchyard in the
village of Parton in Scotland.
|