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Promoting Irish Culture and History from Little Rock, Arkansas, USA


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Death of Mathematician Sir William Rowan Hamilton

Sir William Rowan Hamilton, Irish mathematician, Andrews Professor of Astronomy at Trinity College, Dublin, and Royal Astronomer of Ireland, who makes important contributions to classical mechanics, optics, and algebra, dies in Dublin on September 2, 1865, following a severe attack of gout.

Hamilton is born in Dublin on August 4, 1805, the fourth of nine children born to Sarah Hutton (1780–1817) and Archibald Hamilton (1778–1819). He is part of a small but well-regarded school of mathematicians associated with Trinity College, Dublin, which he enters at age eighteen. He is said to have shown immense talent at a very early age. Astronomer Bishop Dr. John Brinkley remarks of the 18-year-old Hamilton, “This young man, I do not say will be, but is, the first mathematician of his age.”

Trinity College awards him two Optimes, or off-the-chart grades. He studies both classics and mathematics, and is appointed Professor of Astronomy just prior to his graduation. He then takes up residence at Dunsink Observatory where he spends the rest of his life.

Although Hamilton regards himself as a pure mathematician rather than a physicist, his work is of major importance to physics, particularly his reformulation of Newtonian mechanics, now called Hamiltonian mechanics. This work has proven central to the modern study of classical field theories such as electromagnetism, and to the development of quantum mechanics. In pure mathematics, he is best known as the inventor of quaternions.

Hamilton’s scientific career includes the study of geometrical optics, classical mechanics, adaptation of dynamic methods in optical systems, applying quaternion and vector methods to problems in mechanics and in geometry, development of theories of conjugate algebraic couple functions, solvability of polynomial equations and general quintic polynomial solvable by radicals, the analysis on Fluctuating Functions, linear operators on quaternions and proving a result for linear operators on the space of quaternions, which is a special case of the general theorem which today is known as the Cayley–Hamilton theorem. He also invents Icosian calculus, which he uses to investigate closed edge paths on a dodecahedron that visit each vertex exactly once.

Hamilton retains his faculties unimpaired to the very last, and steadily continues the task of finishing the Elements of Quaternions which occupies the last six years of his life. He dies in Dublin on September 2, 1865, following a severe attack of gout precipitated by excessive drinking and overeating. He is buried in Mount Jerome Cemetery in Dublin.


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Birth of George Francis FitzGerald, Academic & Physicist

Professor George Francis FitzGerald FRS FRSE, Irish academic and physicist, is born at No. 19, Lower Mount Street in Dublin on August 3, 1851. He is known for his work in electromagnetic theory and for the Lorentz–FitzGerald contraction, which becomes an integral part of Albert Einstein‘s special theory of relativity.

FitzGerald is born to the Reverend William FitzGerald and his wife Anne Frances Stoney. He is the nephew of George Johnstone Stoney, the Irish physicist who coins the term “electron.” After the particles are discovered by J. J. Thomson and Walter Kaufmann in 1896, FitzGerald is the one to propose calling them electrons. He is also the nephew of Bindon Blood Stoney, an eminent Irish engineer. His cousin is Edith Anne Stoney, a pioneer female medical physicist.

Professor of Moral Philosophy at Trinity College Dublin and vicar of St. Anne’s, Dawson Street, at the time of his son’s birth, William FitzGerald is consecrated Bishop of Cork, Cloyne and Ross in 1857 and translates to Killaloe and Clonfert in 1862. George returns to Dublin and enters TCD as a student at the age of sixteen, winning a scholarship in 1870 and graduating in 1871 in Mathematics and Experimental Science. He becomes a Fellow of Trinity in 1877 and spends the rest of his career there, serving as Erasmus Smith’s Professor of Natural and Experimental Philosophy from 1881 to 1901.

Along with Oliver Lodge, Oliver Heaviside and Heinrich Hertz, FitzGerald is a leading figure among the group of “Maxwellians” who revise, extend, clarify, and confirm James Clerk Maxwell‘s mathematical theories of the electromagnetic field during the late 1870s and the 1880s.

In 1883, following from Maxwell’s equations, FitzGerald is the first to suggest a device for producing rapidly oscillating electric currents to generate electromagnetic waves, a phenomenon which is first shown to exist experimentally by the German physicist Heinrich Hertz in 1888.

In 1883, FitzGerald is elected Fellow of the Royal Society. In 1899, he is awarded a Royal Medal for his investigations in theoretical physics. In 1900, he is made an honorary fellow of the Royal Society of Edinburgh.

FitzGerald is better known for his conjecture in his short letter to the editor of Science. “The Ether and the Earth’s Atmosphere” explains 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. He bases this idea in part on the way electromagnetic forces are known to be affected by motion. In particular, he uses some equations that had been derived a short time before by his friend the electrical engineer Oliver Heaviside. The Dutch physicist Hendrik Lorentz hits on a very similar idea in 1892 and develops it more fully into Lorentz transformations, in connection with his theory of electrons.

The Lorentz–FitzGerald contraction hypothesis becomes an essential part of the Special Theory of Relativity, as Albert Einstein publishes it in 1905. He demonstrates the kinematic nature of this effect, by deriving it from the principle of relativity and the constancy of the speed of light.

FitzGerald suffers from many digestive problems for much of his shortened life. He becomes very ill with stomach problems. He dies on February 22, 1901 at his home, 7 Ely Place in Dublin, the day after an operation on a perforated ulcer. He is buried in Mount Jerome Cemetery.

A crater on the far side of the Moon is named after FitzGerald, as is a building at Trinity College Dublin.


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Birth of Mathematician William Rowan Hamilton

william-rowan-hamilton

Sir William Rowan Hamilton, Irish mathematician who makes important contributions to classical mechanics, optics, and algebra, is born in Dublin on August 4, 1805.

Hamilton is the fourth of nine children born to Sarah Hutton (1780–1817) and Archibald Hamilton (1778–1819). He is part of a small but well-regarded school of mathematicians associated with Trinity College, Dublin, which he enters at age eighteen. He is said to have shown immense talent at a very early age. Astronomer Bishop Dr. John Brinkley remarks of the 18-year-old Hamilton, “This young man, I do not say will be, but is, the first mathematician of his age.”

Trinity College awards him two Optimes, or off-the-chart grades. He studies both classics and mathematics, and is appointed Professor of Astronomy just prior to his graduation. He then takes up residence at Dunsink Observatory where he spends the rest of his life.

Although Hamilton regards himself as a pure mathematician rather than a physicist, his work is of major importance to physics, particularly his reformulation of Newtonian mechanics, now called Hamiltonian mechanics. This work has proven central to the modern study of classical field theories such as electromagnetism, and to the development of quantum mechanics. In pure mathematics, he is best known as the inventor of quaternions.

Hamilton’s scientific career includes the study of geometrical optics, classical mechanics, adaptation of dynamic methods in optical systems, applying quaternion and vector methods to problems in mechanics and in geometry, development of theories of conjugate algebraic couple functions, solvability of polynomial equations and general quintic polynomial solvable by radicals, the analysis on Fluctuating Functions, linear operators on quaternions and proving a result for linear operators on the space of quaternions, which is a special case of the general theorem which today is known as the Cayley–Hamilton theorem. He also invents Icosian calculus, which he uses to investigate closed edge paths on a dodecahedron that visit each vertex exactly once.

Hamilton retains his faculties unimpaired to the very last, and steadily continues the task of finishing the Elements of Quaternions which occupies the last six years of his life. He dies on September 2, 1865, following a severe attack of gout precipitated by excessive drinking and overeating. He is buried in Mount Jerome Cemetery in Dublin.