James Clerk Maxwell (1831–1879) was a Scottish mathematician and theoretical physicist from Edinburgh, Scotland. His most significant achievement was aggregating a set of equations in electricity, magnetism and inductance—eponymously named Maxwell's equations—including an important modification (extension) of the Ampère's Law. It was the most unified model of electromagnetism yet. It is famous for introducing to the physics community a detailed model of light as an electromagnetic phenomena, building upon the earlier hypothesis advanced by Faraday (Faraday Effect).
He also developed the Maxwell distribution, a statistical means to describe aspects of the 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 special relativity and quantum mechanics. He is also known for creating the first true color photograph in 1861.
Maxwell demonstrated that electric and magnetic fields 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 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.
Maxwell is considered by many physicists 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.
Maxwell’s Equations
In electromagnetism, Maxwell's equations are a set of four equations that were first presented as a distinct group in 1884 by Oliver Heaviside in conjunction with Willard Gibbs. These equations had appeared throughout Maxwell's 1861 paper entitled On Physical Lines of Force.
They describe the interrelationship between electric fields, magnetic fields, electric charge, and electric current, and although Maxwell himself was the originator of only one of these equations (by virtue of modifying an already existing equation), he derived them all again independently in conjunction with his molecular vortex model of Faraday's lines of force.
Maxwell introduced an extra term to Ampère's circuital law which is the time derivative of electric field and known as Maxwell's displacement current. This modification is the most significant aspect of Maxwell's work in electromagnetism.
In Maxwell's 1865 paper, A Dynamical Theory of the Electromagnetic Field Maxwell's modified version of Ampère's circuital law enabled him to derive the electromagnetic wave equation, hence demonstrating that light is an electromagnetic wave.