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Oliver Heaviside (May 18, 1850 – February 3, 1925) was a self-taught English electrical engineer, mathematician and physicist who adapted complex numbers to the study of electrical circuits, developed techniques for applying Laplace transforms to the solution of differential equations, reformulated Maxwell's field equations in terms of electric and magnetic forces and energy flux, and independently co-formulated vector analysis. Although at odds with the scientific establishment for most of his life, Heaviside changed the face of mathematics and science for years to come.
Early years Heaviside was born in London's Camden Town. He was short and red-headed, and suffered from scarlet fever during his youth. The illness had a lasting impact on him, and Heaviside was left partially deaf. Although he was a good scholar (placed fifth out of five hundred students in 1865), he left school at 16 and began learning about Morse code and electromagnetism. Heaviside became a telegraph operator, initially in Denmark and, later, at the Great Northern Telegraph Company. Heaviside continued to study and, in 1872, while working as a chief operator in Newcastle upon Tyne, he started an analysis of electricity. In 1874, Heaviside left this position and researched in isolation at his parents' house. Here he helped develop transmission line theory (also known as the "telegrapher's equations"). Heaviside showed mathematically that uniformly distributed inductance in a telegraph line would diminish both attenuation and distortion, and that, if the inductance were great enough and the insulation resistance not too high, the circuit would be distortionless while currents of all frequencies would be equally attenuated. Heaviside's equations helped further the implementation of the telegraph. Middle years In 1880, Heaviside researched the skin effect in telegraph transmission lines. Heaviside, after 1880, recast Maxwell's mathematical analysis from its original cumbersome form (also recast as quaternions) to its modern vector terminology, thereby reducing the original twenty equations in twenty unknowns down to the four differential equations in four unknowns we now know as Maxwell's equations. The four re-formulated Maxwell's equations describe the nature of static and moving electric charges and magnetic dipoles, and the relationship between the two, namely electromagnetic induction. Between 1880 and 1887, Heaviside developed the operational calculus (involving the D notation for the differential operator, which he is credited with creating), a method of solving differential equations by transforming them into ordinary algebraic equations which caused a great deal of controversy when first introduced, owing to the lack of rigour in his derivation of it. He famously said, "Mathematics is an experimental science, and definitions do not come first, but later on." He was replying to criticism over the use of operators that weren't clearly defined. In 1887, Heaviside proposed that induction coils (inductors) should be added to the transatlantic telegraph cable (increasing self-induction) in order to correct the distortion which it suffered. For political reasons, this was not done. Michael Idvorsky Pupin later devised a means of extending the range of long-distance telephone communication, by placing loading coils at intervals along the transmitting wire, which followed up on the ideas of Heaviside's research. In two papers of 1888 and 1889, Heaviside calculated the deformations of electric and magnetic fields surrounding a moving charge, as well as the effects of it entering a denser medium. This included a prediction of what is now known as Cherenkov radiation, and inspired Fitzgerald to suggest what now is known as the Lorentz-Fitzgerald contraction. Around 1889, after Joseph John Thomson's research into the electron, Heaviside worked on the concept of electromagnetic mass. Heaviside treated this as "real" as material mass, capable of producing the same effects. Wilhelm Wien later verified Heaviside's expression (for low velocities). In 1891 the British Royal Society recognized Heaviside's contributions to the mathematical description of electromagnetic phenomena by naming him a Fellow of the Royal Society. In 1905 Heaviside was given an honorary doctorate by the University of Göttingen. Later years In 1902, Heaviside proposed the existence of the Kennelly-Heaviside Layer of the ionosphere which bears his name. Heaviside's proposal included means by which radio signals are transmitted around the earth's curvature. The existence of the ionosphere was confirmed in 1923. The predictions by Heaviside, combined with Planck's radiation theory, probably discouraged further attempts to detect radio waves from the Sun and other astronomical objects. For whatever reason, there seem to have been no attempts for 30 years, until Jansky's development of radio astronomy in 1932. In later years his behaviour became quite eccentric, having been at odds with the scientific establishment for most of his life. Though he had been an active cyclist in his youth, his health seriously declined in his sixth decade. During this time Heaviside would sign correspondences with the initials "W.O.R.M." after his name though the letters did not stand for anything. Heaviside also started painting his fingernails pink and had granite blocks moved into his house for furniture. Heaviside died at Torquay in Devon, and is buried in Paignton cemetery. Most of his recognition was gained posthumously. Innovations and discoveries Heaviside advanced the idea of the ionosphere, making the prediction of the Kennelly-Heaviside Layer. Heaviside developed the transmission line theory (also known as the "telegrapher's equations"). Heaviside independently co-discovered the poynting vector. Heaviside simplified and made useful for the sciences the original Maxwell's equations of electromagnetism. This innovation from the reformulation of Maxwell's original equations gives the four vector equations known today. Heaviside developed the Heaviside step function, which he used to model the flow of current in an electric circuit. Heaviside developed vectors (and vector calculus). Heaviside formed the operator method for linear differential equations. Electromagnetic terms Oliver Heaviside coined the following terms: See also Publications Further reading Sorted by date. a biography". London, 1963. | ||||||||
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