Hamilton Day
Hamilton Day commemorates a ground-breaking discovery by one of Ireland’s most famous scientists, William Rowan Hamilton (1805–65).
Hamilton Day (16 October)
Hamilton Day commemorates a ground-breaking discovery by one of Ireland’s most famous scientists. On 16 October 1843, Irish mathematician William Rowan Hamilton MRIA and his wife Helen were walking along the banks of the Royal Canal from Dunsink Observatory on their way to the Royal Irish Academy.
At Broome Bridge, William had a eureka moment and came up with a new algebra he called quaternions. So excited was he by his discovery, he scratched the fundamental formula i² = j² = k² = ijk = −1 onto the bridge with his penknife. His quaternions revolutionised algebra and would later help to put a man on the moon and be used for CGI in movies.
Hamilton Day on 16 October is commemorated annually by the Academy through an award ceremony that recognises the most gifted third level mathematics students in Ireland, and the Hamilton Lecture is given by an internationally renowned speaker, who also delivers a masterclass for early-career researchers.
Hamilton Day is supported by 
Who is Hamilton?
William Rowan Hamilton (1805–65) is universally recognised as the greatest mathematician, and arguably the greatest scientist, that Ireland has produced to date.
Latest Hamilton Day updates
Hamilton Prize in Mathematics
Each year on Hamilton Day, the Academy recognises the most gifted third level mathematics students in Ireland, hosts a masterclass for early-career researchers and the day concludes with the Hamilton Lecture which is given by an internationally renowned speaker.
Hamilton Did It
Hamilton Did It was an artwork project that commemorated William Rowan Hamilton’s Eureka moment at Broombridge.
In 2018, the RIA, Transport Infrastructure Ireland and TU Dublin (formerly DIT) ran a curated competition open to staff, alumni and students of the TU Dublin School of Creative Arts at the newly opened city centre campus in Grangegorman.
Applications were invited for artworks to commemorate that Eureka moment which Hamilton had on 16 October 1843. The winner of this publically funded commission was former Fine Art student, Emma Ray, who designed an artwork commemorating Hamilton’s groundbreaking graffiti at Broombridge Luas stop. The artwork was officially launched in 2019.
