George FitzGerald
Encyclopedia
George Francis FitzGerald (3 August 1851 – 22 February 1901) was an Irish
Irish people
The Irish people are an ethnic group who originate in Ireland, an island in northwestern Europe. Ireland has been populated for around 9,000 years , with the Irish people's earliest ancestors recorded having legends of being descended from groups such as the Nemedians, Fomorians, Fir Bolg, Tuatha...

 professor of "natural and experimental philosophy" (i.e., physics) at Trinity College
Trinity College, Dublin
Trinity College, Dublin , formally known as the College of the Holy and Undivided Trinity of Queen Elizabeth near Dublin, was founded in 1592 by letters patent from Queen Elizabeth I as the "mother of a university", Extracts from Letters Patent of Elizabeth I, 1592: "...we...found and...

 in Dublin, Ireland, during the last quarter of the 19th century.

His Life and His Work in Physics

FitzGerald was born at No. 19, Lower Mount Street in Dublin on 3 August 1851 to the Reverend William FitzGerald
William Fitzgerald (bishop)
William Fitzgerald was an Anglican bishop, first of Cork, Cloyne and Ross and then of Killaloe and Clonfert.Fitzgerald, son of Maurice Fitzgerald, M.D., by his second wife, Mary, daughter of Edward William Burton of Clifden, county Galway, and younger brother of Francis Alexander Fitzgerald, third...

 and his wife Anne Francis Stoney. Professor of Moral Philosophy in Trinity and vicar of St Anne's, Dawson Street, at the time of his son's birth, William FitzGerald was consecrated Bishop of Cork, Cloyne and Ross
Bishop of Cork, Cloyne and Ross
The Bishop of Cork, Cloyne and Ross is the Church of Ireland Ordinary of the united Diocese of Cork, Cloyne and Ross in the Province of Dublin....

 in 1857 and translated
Translation (ecclesiastical)
Translation is the technical term when a Bishop is transferred from one diocese to another.This can be* From Suffragan Bishop status to Diocesan Bishop*From Coadjutor bishop to Diocesan Bishop*From one country's Episcopate to another...

 to Killaloe and Clonfert
Bishop of Killaloe and Clonfert
The Bishop of Killaloe and Clonfert was the Ordinary of the Church of Ireland diocese of Killaloe and Clonfert; comprising all of County Clare and part of counties of Tipperary, Galway and Roscommon, Ireland.-History:Under the Church Temporalities Act 1833, the Episcopal see was a union of the...

 in 1862. George returned to Dublin and entered Trinity as a student at the age of 16. He became a Fellow of Trinity in 1877 and spent the rest of his career at this college.

Along with Oliver Lodge, Oliver Heaviside
Oliver Heaviside
Oliver Heaviside was a self-taught English electrical engineer, mathematician, and physicist who adapted complex numbers to the study of electrical circuits, invented mathematical techniques to the solution of differential equations , reformulated Maxwell's field equations in terms of electric and...

 and Heinrich Hertz, FitzGerald was a leading figure among the group of "Maxwellians" who revised, extended, clarified, and confirmed James Clerk Maxwell
James Clerk Maxwell
James Clerk Maxwell of Glenlair was a Scottish physicist and mathematician. His most prominent achievement was formulating classical electromagnetic theory. This united all previously unrelated observations, experiments and equations of electricity, magnetism and optics into a consistent theory...

's mathematical theories of the electromagnetic field
Electromagnetic field
An electromagnetic field is a physical field produced by moving electrically charged objects. It affects the behavior of charged objects in the vicinity of the field. The electromagnetic field extends indefinitely throughout space and describes the electromagnetic interaction...

 during the late 1870s and the 1880s.

In 1883, following from Maxwell's equations
Maxwell's equations
Maxwell's equations are a set of partial differential equations that, together with the Lorentz force law, form the foundation of classical electrodynamics, classical optics, and electric circuits. These fields in turn underlie modern electrical and communications technologies.Maxwell's equations...

, FitzGerald suggested a device for producing rapidly oscillating electric currents to generate electromagnetic waves, a phenomenon which was first shown to exist experimentally by the German physicist Heinrich Hertz in 1888.

FitzGerald suffered from many digestive problems for much of his shortened life. He became very ill with stomach problems and died after an operation on a perforated ulcer at his home in Dublin on 21 February 1901.

FitzGerald was also the nephew of George Johnstone Stoney
George Johnstone Stoney
George Johnstone Stoney was an Irish physicist most famous for introducing the term electron as the "fundamental unit quantity of electricity"....

, the Irish physicist who coined the term "electron". After the particles were discovered by J. J. Thomson
J. J. Thomson
Sir Joseph John "J. J." Thomson, OM, FRS was a British physicist and Nobel laureate. He is credited for the discovery of the electron and of isotopes, and the invention of the mass spectrometer...

 and Walter Kaufmann
Walter Kaufmann (physicist)
Walter Kaufmann was a German physicist. He is most well known for his first experimental proof of the velocity dependence of mass, which was an important contribution to the development of modern physics, including special relativity.-Life:In 1890/91 he studied mechanical engineering at the...

 in 1896, FitzGerald was the one to propose calling them electrons.
Length contraction=

FitzGerald is better known for his conjecture in his short paper "The Ether and the Earth's Atmosphere" (1889) that if all moving objects were foreshortened in the direction of their motion, it would account for the curious null-results of the Michelson-Morley experiment
Michelson-Morley experiment
The Michelson–Morley experiment was performed in 1887 by Albert Michelson and Edward Morley at what is now Case Western Reserve University in Cleveland, Ohio. Its results are generally considered to be the first strong evidence against the theory of a luminiferous ether and in favor of special...

. FitzGerald based this idea in part on the way electromagnetic forces were known to be affected by motion. In particular, FitzGerald used some equations that had been derived a short time before by his friend the electrical engineer Oliver Heaviside
Oliver Heaviside
Oliver Heaviside was a self-taught English electrical engineer, mathematician, and physicist who adapted complex numbers to the study of electrical circuits, invented mathematical techniques to the solution of differential equations , reformulated Maxwell's field equations in terms of electric and...

. The Dutch
Dutch people
The Dutch people are an ethnic group native to the Netherlands. They share a common culture and speak the Dutch language. Dutch people and their descendants are found in migrant communities worldwide, notably in Suriname, Chile, Brazil, Canada, Australia, South Africa, New Zealand, and the United...

 physicist Hendrik Lorentz
Hendrik Lorentz
Hendrik Antoon Lorentz was a Dutch physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for the discovery and theoretical explanation of the Zeeman effect...

 hit on a very similar idea in 1892 and developed it more fully into Lorentz transformations, in connection with his theory of electrons.

The FitzGerald-Lorentz contraction (or Lorentz-FitzGerald contraction hypothesis) became an essential part of the Special Theory of Relativity, as Albert Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...

 published it in 1905. He demonstrated the kinematic nature of this effect, by deriving it from the principle of relativity
Principle of relativity
In physics, the principle of relativity is the requirement that the equations describing the laws of physics have the same form in all admissible frames of reference....

 and the constancy of the speed of light.

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