William Rowan Hamilton

Sir William Rowan Hamilton FRAS
Born	(1805-08-04)4 August 1805 Dublin, Ireland
Died	2 September 1865(1865-09-02) (aged 60) Dublin, Ireland
Alma mater	Trinity College Dublin
Known for	Hamiltonian mechanics (1833) Hamilton's principle (1834) Describing quaternions (1843) Coining the term tensor (1846) Inventing icosian calculus (1856) Inventing the icosian game (1856)
Spouse	Helen Marie Bayly ​ (m. 1833)​
Children	3, including William
Relatives	Eliza Mary Hamilton (sister)
Awards	Cunningham Medal (1834, 1848) Royal Medal (1835)
Honours	Knight Bachelor (1835)
Scientific career
Fields	Astronomy mathematics physics
Institutions	Trinity College Dublin Dunsink Observatory
Academic advisors	John Brinkley
3rd Andrews Professor of Astronomy
In office 1827–1865
Preceded by	John Brinkley
Succeeded by	Franz Brünnow

Sir William Rowan Hamilton (4 August 1805 – 2 September 1865)^[1][2] was an Irish astronomer, mathematician, and physicist who made numerous major contributions to abstract algebra, classical mechanics, and optics. His theoretical works and mathematical equations are considered fundamental to modern theoretical physics, particularly his reformulation of Lagrangian mechanics. His career included the analysis of geometrical optics, Fourier analysis, and quaternions, the last of which made him one of the founders of modern linear algebra.^[3]

Hamilton was Andrews Professor of Astronomy at Trinity College Dublin. He was also the third director of Dunsink Observatory from 1827 to 1865. The Hamilton Institute at Maynooth University is named after him.