The Hamilton Year 2005 at DIT

Who was William Rowan Hamilton?

"He used to carry on, long trains of algebraic and arithmetical calculations in his mind, during which he was unconscious of the earthly necessity of eating; we used to bring in a ‘snack’ and leave it in his study, but a brief nod of recognition of the intrusion of the chop or cutlet was often the only result, and his thoughts went on soaring upwards."

— William Edwin Hamilton (his elder son)


Sir William Rowan Hamilton (1805-1865) was an Irish physicist, and astronomer and one of the world's great mathematicians. Born at midnight on August 3, 1805, he spent his entire life in the environs of Dublin.

A child prodigy, his genius first displayed itself in the form of a wonderful power of acquiring languages. As a child, his linguist uncle James taught him 14 languages (Bell 1986, p. 341).

At the age of 17 Hamilton taught himself mathematics. Dr. John Brinkley, Bishop of Cloyne, is said to have remarked in 1823 of an eighteen year old Hamilton: “This young man, I do not say will be, but is, the first mathematician of his age.

Hamilton’s career at university was perhaps unexampled. Amongst a number of competitors of more than ordinary merit, he was first in every subject and at every examination. He achieved the rare distinction of obtaining an optime for both Greek and for physics. In fact Hamilton became Andrews Professor of Astronomy in Trinity College Dublin even before he had completed his undergraduate degree.

Hamilton discovered an error in Laplace's Celestial Mechanics. He predicted conical refraction in biaxial crystals, which was soon experimentally observed by Lloyd. Hamilton also extended the least action principle described earlier by Maupertuis. His work in physics proved significant for the development of quantum mechanics. Hamiltonian mechanics is used today to determine orbital trajectories of satellites and was used for the recent Mars mission.

He is best known however for his discovery in 1843 of quaternions, an important mathematical expression used in describing 3D spaces in computer graphics. As he passed Broombridge he etched the formula into the stone parapet of the bridge.

Hamilton died in 1865 but he remains today a towering figure in mathematics. He was deeply interested in philosophy and enjoyed writing poetry, being a close friend of Wordsworth. Knighted in 1835, he was the first foreign member elected to the National Academy of Science (USA) in 1865.